By Karen Rosen | June 26, 2017, 4:49 p.m. (ET)

SACRAMENTO, Calif. – Forged in heat and shaped by talent and perseverance, Team USA stands ready to compete at the IAAF World Championships in London Aug. 4-13.

While there are many familiar faces on the squad, other athletes are newer to the world stage.

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Team USA led all countries with 18 medals in at the 2015 worlds in Beijing – with six of each color. The gold medals came from the men’s 4x400-meter team, Christian Taylor (triple jump), Joe Kovacs (shot put), Allyson Felix (400-meter), Tianna Bartoletta (long jump) and Ashton Eaton (decathlon). Only Eaton, a two-time Olympic and two-time world champion, has retired.

Here are 10 takeaways from the 2017 USATF Outdoor Championships:

 

1) Experience Pays Off Big Time...

There are oldies but goodies on the team. Thirty-five-year-old Justin Gatlin won the 100-meter in a duel with 21-year-old Christian Coleman. Gatlin made his fourth world championships team and is the reigning silver medalist in the 100.

Trey Hardee, despite a foot injury that pains him on 9 of his 10 events, won the decathlon as he seeks a third world title. Hardee won in 2009 and 2011 and was the 2012 Olympic silver medalist on the same track in London.

Aries Merritt, who will be 32 next month, has been revitalized by his new kidney. Merritt, the 2012 Olympic champion and world-record holder, revealed prior to the 2015 worlds that he needed a kidney transplant. Even with severely diminished kidney function, he won the bronze medal in Beijing. What can he do now that he feels like himself again?

“No matter what someone may tell you, whether it’s a doctor or not, you can’t give up hope,” Merritt said. “You always have to stay positive and look at the brighter picture.”

LaShawn Merritt, who celebrates his 31st birthday on Tuesday, will race the 400. He had a wild card into worlds thanks to his Diamond League crown, and is ready to take on Fred Kerley, the newest young gun in the event.

Felix, the reigning 400-meter champ, is 31. She will try to add to her 13-medal world championships collection, which includes nine golds. This is Felix’s seventh world team going back to 2005.

Among the other 30-somethings in London: Olympic gold and silver medalist Dawn Harper-Nelson, the fourth qualifier in the 100-meter hurdles and 2011 world bronze medalist, is 33; Molly Huddle, who won the 10,000 and also qualified in the 5,000, is 32; Shannon Rowbury, runner-up in the 5K, is also 32; Kerron Clement, the 400-meter hurdles Olympic champion who was seventh in Sacramento, but had the safety net of his wild card as Diamond League champ, is 31; Bartoletta is 31 and her long jump rival Brittney Reese is 30; Natasha Hastings, who made the relay pool in the 400, will be 31 in July; Jenny Simpson, the 1,500 winner, is 30, while Sara Vaughn, who grabbed the last spot in the 1,500, is 31 and the mother of three.

Sharon Day-Monroe, 32, was the third qualifier in the heptathlon. In 2008, she was an Olympic high jumper, then made the world team in 2009 in the heptathlon. This is her fifth world outdoor championships in the event. “I couldn’t be prouder to represent Team USA with these talented young girls,” she said. “When I do decide to retire, I’ll know the sport and the event is in good hands.”

 

2) ...But Not In Every Case

Some veterans won't be in London after falling short in Sacramento. Among them are Tyson Gay (100 and 200), Nick Symmonds (800), Bershawn Jackson (400 hurdles), Chaunte Lowe (high jump), Shalane Flanagan (10,000), Galen Rupp (10,000), David Oliver (110 hurdles), Jeff Henderson (long jump), Wallace Spearmon Jr. (200), Walter Dix (200), Lopez Lomong (5,000) and Stephanie Brown Trafton (discus).

“We don’t realize our legacy until years down the road,” said Brown Trafton, the 2008 Olympic gold medalist. “I feel like my legacy is the young throwers who have said they were inspired when they saw me on TV. There’s not an age limit in this event, but I want to get on with the rest of my life. I can still be a part of the sport and try to make it better for athletes and fans.”

 

3) Collegians Are Making A Big Leap

College stars are stepping up to the world stage. Christian Coleman, who swept the NCAA sprints for Tennessee, was second in both the 100 and the 200. He has the world-leading time this season in the 100 (9.82 seconds) and the second-best time in the 200 (19.85). Deajah Stevens, who didn’t win any individual titles for Oregon, won the 200 for her first national crown and was second in the 100. Fred Kerley, who has dominated the 400 for Texas A&M, continued to beat all rivals and has the top five times in the world this season, led by his 43.70 in May. Raven Saunders, who won three NCAA titles in the shot put for Ole Miss, tossed a world-leading mark and defeated Olympic champion Michelle Carter.

And siblings Kendell and Devon Williams of Georgia are the first siblings to make the world team in the heptathlon and decathlon. Kendell, a 2016 Olympian, won the heptathlon while Devon, who is about 17 months older, was third in the decathlon.

They were the first siblings to win the multi-events at the 2017 indoor NCAA meet. Kendell Williams then won her third NCAA outdoor heptathlon crown while her brother was second in the NCAA decathlon.

 

4) Wonder Women Abound

The sport showed its love to two Wonder Women. Gabriele Grunewald, in the midst of chemotherapy as she fights cancer for the fourth time, gamely ran the 1,500-meter. Though she lagged further and further behind in her heat, she finished last to the cheers of the crowd. Grunewald then lingered at Hornet Stadium long after the race, laughing and posing for pictures.

"It's so meaningful to be here this weekend,” she said. “This is definitely the end of a journey for me that has been full of ups and downs, but it's been so overwhelming to have the support of the track and field community. I'm just grateful to have so many people out here tonight who really care what I'm going through, and I hope that other people can see that I'm trying to be the best example that I can be of somebody who's trying to persevere through something difficult.

“I'm super grateful for the support, and I hope I can be back in the future and not running on chemo and be cancer free – that’s the goal."

Alysia Montano, the six-time 800-meter champ, became a two-time competitor while pregnant. Montano, who is due in November, grinned as she went to the starting line and was still smiling when she finished. Montano wore a Wonder Woman top that she bought because she was “super stoked” by the movie. She finished more than 10 seconds faster than she did in 2014, when she was 34 weeks pregnant.

 

5) Too Hot To Handle

Sometimes the heat wins. The temperature in Sacramento, which reached as high as 110 degrees, took one high-profile victim: Clayton Murphy, the 800-meter Olympic bronze medalist who was attempting the rare 800/1,500 double. Murphy ran rounds of both on Thursday, the 800-meter semifinals on Friday and the 1,500 final on Saturday. He was last in the 1,500 and was limping after the race. He could not even attempt the 800 final on Sunday, where he was a clear favorite. “Both of Clayton’s hamstrings cramped up on him with about 250 meters to go in the 1,500 meters,” said his agent, Paul Doyle. “He couldn’t get them to loosen up and had to scratch today’s 800-meter final.”

 

6) Move Over, 100-Meter Hurdlers

Team USA has sweep potential in both women's hurdles events. The 400-meter hurdles final was blazing hot, with the top three running under the elusive 53-second mark. Olympic champion Dalilah Muhammad was first in 52.64, followed by Shamier Little in 52.75 and Kori Carter in 52.96, while Olympic bronze medalist Ashley Spencer was the odd woman out in 53.11, which would have won the U.S. title every year except 1997 and 2016. Cassandra Tate, the 2015 bronze medalist and Diamond League champion, has the wild card in the event. On the IAAF “top list,” Team USA boasts the top 6 performers and the top 15 performances.

“I knew it was going to be fast,” Carter said, “with all the talent we’ve got in this event. How are we going to do in London? Not to jinx us, but we can’t have only the 100-meter hurdlers doing sweeps.”

While not quite as dominant as last year, Team USA is also lighting up the world list in the 100-meter hurdles. The United States swept the event in Rio and could go 1-2-3-4 in London. World-record holder Keni Harrison, whose broken left hand has healed, won in Sacramento, followed by Olympic silver medalist Nia Ali, Christina Manning and Harper-Nelson. Unfortunately, Jasmin Stowers, who posted the world leading time of 12.47 in the semis, will stay home. Ali posted the second-fastest time, also in the semifinals, of 12.52, followed by Harrison’s 12.54. Brianna Rollins, the Olympic gold medalist, is serving a doping suspension for failing to report her whereabouts.

 

7) Rivalries Are On Hold

Some showdowns will have to wait. Bartoletta and Kovacs went head-to-head with their rivals despite having wild cards into worlds as defending champions. Bartoletta, the reigning Olympic champion, defeated Reese, the 2012 champ, in a long jump duel while Kovacs lost to Olympic gold medalist Ryan Crouser on the final throw.

“I don’t care about the wild card; I’m looking at winning championships,” Bartoletta said. “There’s no bigger stimulus than this. Brittney makes me remain present for every moment because she can always unleash a huge jump.”

Added Reese, “It’s always revenge with me and Tianna. I got her at Pre, she got me here. We’ve gone back and forth all year long, which is good for our sport.”

Other matchups, however, did not materialize. Two-time Olympic champ Christian Taylor, who won an epic clash with Will Claye at the Prefontaine Classic, opted to intentionally foul in the triple jump – enough to satisfy USATF requirements. While he watched, Claye, the two-time Olympic silver medalist, went a personal best of 58 feet, 9 ¼ inches.

“I’ve won every meet this year,” said Taylor, who has upcoming competitions in Ostrava, Czech Republic, and Paris. “I’m definitely healthy, but it’s definitely unfortunate. Every time I compete I want to put on a show, but this time I had to play it smart. I want to bring home to the U.S. a medal, and that’s what everyone’s fighting for.”

Quanera Hayes won the 400 in a world-leading time of 49.72, while Phyllis Francis also broke 50 seconds with a time of 49.96. Felix will be waiting for them in London.

LaShawn Merritt ran only one round of the 200 to show his fitness. He has a wild card in the 400, where he will face a new rival in Kerley.

 

8) Size Isn’t Everything

Sam Kendricks can do more with a shorter pole than anyone else. Kendricks, the Olympic silver medalist, posted a world leading mark and finally cleared the coveted 6 meters.

“Six meters is a career point,” said Kendricks, who uses a pole that is nearly a foot shorter than those used by most world-class vaulters. “Every great jumper has at least one six-meter jump. Imperially, nineteen eight and a quarter doesn’t sound great, but six meters does. If I can replicate even close to this at worlds, I’ve got a shot at the title. Going for the gold in London is my goal.”

 

9) Better Safe Than Sorry When It Comes To Food

Ajee Wilson has banned beef from her diet. Wilson, who won a thrilling 800-meter, lost her American indoor record after the United States Anti-Doping Agency said she tested positive for a prohibited substance that was ingested through contaminated meat. However, Wilson escaped suspension. “I know myself. I know my heart. I know what happened,” she said.

 

10) On To The (Even) Big(ger) Meet

London is calling. Said Drew Windle, who was third in the men’s 800. “This makes all the stress and wanting to puke after practice and races all worth it.”