What Happened on Day 7 (Aug. 27 evening - Aug. 28 morning): Two-time defending decathlon World Champion Ashton Eaton bookended his day with record breaking results, while 2013 IAAF 1,500 meter silver medalist Matthew Centrowitz advanced to the finals with ease.

Experience reigned supreme on the seventh day of the IAAF World Championships, with two of the most accomplished former Ducks putting themselves in prime positions for repeat medal performances.

Eaton took charge right away, winning three of five events in his first decathlon in two years. He overcame a poor start in the 100 meters, the day's first event, to win in a IAAF World Championship decathlon record 10.23 seconds. It was Eaton's second-best mark of all-time, trailing only his 10.21 world decathlon record from the 2012 Olympic Trials.

He jumped 25-10.25 (7.88m) in the long jump, the best in the field, and threw 47-7.75 (14.52m) in the shot put to extend his lead over Canada's Damian Warner to 83 points after three events. A 6-7 (2.01m) clearance in the high jump set the stage for a historic close to the competition's first day.

In the final event, the 400 meters, Eaton used his experience racing the 400 meter hurdles over the last year and dramatically pulled away from the field over the final 200 meters to finish in 45.00, breaking the decathlon world record set at the 1968 Olympics in Mexico City by an astonishing .68 seconds.

The addition of the remarkable 1,060 points from the 400 brought Eaton's first day total to 4,703, the second-best of his career and just 25 points behind his 2012 Olympic Trials world record pace. He leads Canada's Damian Warner by 173 points.

In the 1,500 meter semifinals earlier in the day, Centrowitz, the 2011 NCAA Champion, went to the front early in the race and remained there nearly the entire way. In a very tactical heat, the leaders passed 800 meters in 2:08 before a fast last 300 meters propelled him to a fourth place finish in 3:43.97, an automatic qualifying position to Sunday's final. It is the fourth-straight World and Olympic Championship final for Centrowitz, who medaled at the last two World Championships.

What to Watch on Day 8 (Aug. 28 evening – Aug. 29 morning): After an outstanding first day, Eaton returns Friday night as the leader for the second day of the decathlon in prime position to defend his World Championship title. Trey Hardee, the U.S. Champion who was expected to give Eaton his greatest challenge, was forced to withdraw from the competition after the high jump due to an injury he sustained in the long jump. Damian Warner, the Canadian Champion who won bronze at the 2013 World Championship, sits 173 points behind Eaton. Perhaps the greatest challenger, as it was so many times in Eaton's historic collegiate career at Oregon, are the record books that will surely undergo an assault starting this evening. His first day total of 4,703 puts him on pace to break his 9,039 world record, but Eaton will need strong performances in the discus and pole vault to remain in reach.

Also Friday night, Phyllis Francis, who won a World Relays Gold Medal as part of the U.S. 4x400 meter squad earlier this spring, is expected to race in the opening round heats tonight. Francis placed seventh in the open 400 meters final on Thursday and ran an outdoor personal best 50.50 during the semifinals. At the World Relays, she led the U.S. team during the qualifying round with a 49.74 split and then ran the opening leg in the final. The United States enters the competition with the fastest time in the world this year and should qualify for the final with ease. Great Britain and France are the top challengers in the Americans' heat. In the other heat, Jamaica is the top seed.

For the first time, a trio of Ducks could take to the track for the United States in the 4x100 meter relay, with both the qualification heats and finals contested over the next 24 hours. Jasmine Todd and English Gardner both advanced to the 100 meter semifinals earlier this week, and Jenna Prandini placed sixth in the U.S. Championships 100 meter final before winning the 200 meter title in June. All three raced on the 4x100 relay teams at the Monaco Diamond League in July, with Prandini and Gardner combining to run a world-leading 41.96. The last time three alumni from one school ran on the same IAAF relay was 2011 with three runners from the University of Texas.

The United States team, which set the world record in the 2012 Olympic final, has won the gold medal at three of the last five World Championships. While the U.S. is the only squad to run under :42 this year, four countries in Team USA's heat have broken :43 in 2015 - Ukraine, the Netherlands, Trinidad and Tobago, and Brazil. As in the 4x400 relay, Jamaica is the top seed in the other heat.

Early risers on Saturday can catch the 4x100 meter final at 5:50 a.m. PT.
 
Also early Saturday, Galen Rupp returns to the track for the third time at this World Championship for the 5,000 meter final. He placed fifth in the 10,000 meters earlier this week and will look to move up in this event, after a seventh place finish at the 2012 Olympics. Although he has only run under 13:00 once in his career, his tactical racing experience and fast closing speed will help him contend for the title here. The favorite is his training partner, two-time defending champion Mo Farah who won the 10,000 meter title a week ago.

August 28:
TV Coverage: Universal Sports 4:30 – 9:30 PM LIVE
                6:00 PM – Decathlon 110m Hurdles (Eaton)
                7:05 PM – Decathlon Discus (Eaton)
                7:15 PM – Women's 4x400m Relay Heats (Francis)
                9:00 PM – Women's 4x100m Relay Heats (Prandini, Gardner, Todd)
               10:15 PM - Decathlon Pole Vault (Eaton)

August 29:
TV Coverage: NBC 11:30 AM – 1:00 PM Tape Delayed
Universal Sports 2:00 – 3:30 PM NBC Rebroadcast
                2:00 AM – Decathlon Javelin Throw (Eaton)
                4:30 AM – Men's 5,000m Final (Rupp)
                5:10 AM – Decathlon 1,500m (Eaton)
                5:50 AM – Women's 4x100m Relay (Prandini, Gardner, Todd)