CALI, Colombia — Team USATF's mixed 4x400m relay set a meet record in the prelims and 15 other U.S. athletes advanced to the next round in their events on day one of the World Athletics U20 Championships at Pascual Guerrero Stadium. The American quartet clipped more than a second off the previous meet record of 3:19.70, set last year by Nigeria, clocking 3:18.65 in the second heat. Charlie Bartholomew (McKinney, Texas/USATF Southwestern) teamed up with Madison Whyte (Newport News, Virginia/USATF Virginia), Will Sumner (Canton, Georgia/USATF Georgia) and Kaylyn Brown (Gastonia, North Carolina/USATF North Carolina) to win the heat by more than a second over Jamaica. Facing the toughest competition of his young career, Tyrone Gorze (Central Point, Oregon/USATF Oregon) was in the lead pack through 2km in the men's 5,000m, and Dylan Throop (Edinboro, Pennsylvania/USATF Three Rivers) was in the front of the chase pack. Gorze dropped back to 10th but was still well in contention halfway through the race as the pace surged intermittently. Going past 3km in around 8:47, Gorze bravely tried to stay in touch with the leaders, but with three to go he had a large gap to cover. Losing touch as he went past the finish line with two to go, Gorze was all alone and finished 12th in 14:32.23. Throop did not finish. The meet's first final saw Heidi Nielson (Katy, Texas/USATF Gulf) place 12th in the women's 3,000m in 9:56.35, two places ahead of teammate Kate Peters (Portland, Oregon/USATF Oregon), who crossed the line in 10:05.09. Both American men achieved the short-term goal of advancing to the semifinal in the 110m hurdles despite trouble with the barriers. TJ Caldwell (Pittsburg, Kansas/USATF Missouri Valley) won heat five in 13.73, clattering the ninth hurdle, while Malik Mixon (College Park, Georgia/USATF Georgia) hit the first and fifth barriers hard and wasn't able to regain his rhythm in heat three, but managed to finish third in 14.10 to move on. Two of Team USATF's top medal hopefuls reinforced their status in the women's 800m heats, with high school national record holder Juliette Whittaker (Laurel, Maryland/USATF Potomac Valley) recording the fastest time overall in winning heat three at 2:04.92. Roisin Willis (Stevens Point, Wisconsin/USATF Wisconsin) claimed the runner-up spot in the next section, clocking 2:09.68. Running together in the second heat of the women's 3,000m steeplechase, Karrie Baloga (New Windsor, New York/USATF New York) and Harper McClain (Saint Helena, California/USATF Pacific) earned time qualifier berths in the final. Baloga was sixth in 10:35.33, one spot ahead of McClain's 10:37.05. Laurenz Colbert (Bowie, Maryland/USATF Potomac Valley) and Michael Gizzi (Covington, Georgia/USATF Georgia) easily advanced to the semifinal in the men's 100m, finishing second in their heats. Colbert had the same time as the winner in heat five at 10.39, but was second by .003 seconds, and Gizzi overcame a sluggish start to cruise through in 10.35 in the sixth heat. Nathan Green (Boise,Idaho/USATF Snake River) was tangled up just past the halfway point of the third heat but regained his footing and challenged for the lead into the final lap. Green went wide into the final straight and eased down the stretch to easily qualify for the final with a 3:45.80 in second. Muluken Tewalt (Washington, DC/USATF Potomac Valley) finished 11th in the first heat in 3:56.54 and did not advance. In field event qualifying, both U.S. men made it through to the final of the long jump. Johnny Brackins (Lees Summit, Missouri/USATF Missouri Valley) was the top-ranked entrant and jumped 7.69m/25-2.75 in round two to secure his spot in the final. Curtis Williams (Tallahassee, Florida/USATF Florida) had an opening effort of 7.60m/24-11.25 that was good enough to move him on. Ranked No. 1 in the world coming into the meet, high school record holder Amanda Moll (Olympia, Washington/USATF Pacific Northwest) had to take two attempts at her opening height of 3.95m/12-11.5, but then cleared 4.05m/13-3.5 first time to qualify for the final along with her sister, Hana Moll (Olympia, Washington/USATF Pacific Northwest), who needed only two jumps on the evening to advance. Tarik O'Hagan (Woonsocket, Rhode Island/USATF New England) won two events at the USATF U20 Championships in June and got his world title quest underway with flair, going one and done in the men's shot put with a 19.65m/64-5.75 that surpassed the automatic qualifying mark by two inches. It was a lifetime best with the six-kilogram international implement, adding three centimeters to the mark he set in winning the USATF U20 gold. With a best of 17.44m/57-2.75 on his third attempt, Cade Moran (Murrieta, California/USATF Southern California) finished outside the top 20 and did not make the final. It took her three throws to get going full steam, but Siniru Iheoma (Southampton, Pennsylvania/USATF Mid-Atlantic) hit her best of 50.41/165-4 on her final attempt in the women's discus, the sixth-best throw overall and a ticket to the final. Ames Burton (Manhattan, Kansas/USATF Missouri Valley) threw 46.64m/153-0 and did not advance. Neither American woman in shot put qualifying advanced to the final. Amelia Flynt (Katy, Texas/USATF Gulf) was 14th overall with a best of 14.41m/47-3.5, while Chrystal Herpin (Houston, Texas/USATF Gulf) was 16th at 14.25m/46-9. Elizabeth Bailey (Wildwood, Missouri/USATF Ozark) threw her best of 41.99m/137-9 in round one of the women's javelin and was 16th in qualifying Group A. Join the conversation with USATF on Twitter, Instagram, and Facebook using the hashtag #JourneyToGold. Photo Credit: World Athletics