Three men's javelin throwers set the tone with qualifying marks while Alaka and Williams lead the sprinters.
Texas will provide live streaming coverage of all three days of the Prelims.
Athletes must qualify through the two regional sites to make the final NCAA stop at Eugene.
Freshman Chris Williams took second in the pole vault while also making the hurdles final.
USC hosts the conference championships for the third time and first since 2003.
2012: Outstanding freshman season saw him capture the Pac-12 title and reach the NCAA Championships both indoors and out in the pole vault ... became the third different Husky in four years to win the Pac-12 title, as he vaulted to a new career-high of 17-10 ¼ to get the win in his hometown of Eugene, Ore. in front of family and friends ... that mark moved him into the Husky top-10 list at No. 8 ... followed that win up with another win of sorts at the NCAA West Prelim Championships in Austin, Texas ... though a winner is not crowned at Prelims, Juilfs was the only vaulter out of 48 who was clean up through the final bar needed to advance to the finals in Iowa, winding up with a clearance of 17-8 ½ ... in Des Moines for the NCAA Outdoor Championships, he placed 13th overall with a mark of 17-4 ½, earning All-America Second Team honors ... got another win at Hayward Field when he cleared 17-4 ½ to win the Pepsi Team Invitational ... third in the Mt. SAC Relays open heat, going 16-10 ¾ ... indoors, made the NCAA Indoor Championships on his last possible try, as he cleared 17-8 ¼ at the UW Final Qualifier in the first round of a jump off after initially tying for first ... that 17-8 ¼ mark ranks fifth indoors in school history ... at NCAA Indoors in Nampa, Idaho, he cleared his first bar at 17-0 ¾, but went out at the next height to finish 17th, earning All-America honorable mention ... tied for third at the MPSF Championships, going 17-1 ¾ ... had a big clearance of 17-7 at the UW Invitational, his first over 17-feet in college ... third at the National Pole Vault Summit in Reno, going 16-8 ¾.
High School and Personal: Full name is Jonathon Henry Juilfs ... born in Eugene, Oregon ... parents are Lisa Balint-Juilfs and Pat Juilfs ... has one younger sister, Annie ... the top pole vault recruit in the class of 2011 ... captured the national title at the 2011 USA Junior Championships, clearing a new career-best of 17-2 ¾ to win by more than a foot ... that clearance ranked third in the nation ... won the silver medal at the 2011 Pan-American Junior Championships in Florida, clearing 16-8 ¾ ... got a late start to his senior year after a back injury, but still defended his Oregon 6A state title with a clearance of 16-4 ¾ ... won 10 consecutive meets in the vault as a junior, including capturing the Oregon 6A state championship with a then-PR of 17-0 ¾ ... became the third prep in Oregon state history to clear 17-feet ... was runner-up at the 2009 Oregon state meet in the vault with a 16-0 clearance, and was third as a freshman with a 15-0 clearance ... cleared 16-2 indoors at the 2010 Pole Vault Summit to place fourth ... has also competed at state in the high jump, where he has a 6-2 personal-best, taking seventh at state as a junior ... also ran on the 4x100m relay that placed sixth at the state meet in 2010 ... was a standout football player as well, earning all-Southwest Conference honors as a running back in 2010 and helping his team to the state title in 2009.
2011 USA Jr. Champs - 1st, Pole Vault
2011 Pan-Am Jr. Champs - 2nd, Pole Vault
2012 MPSF - 4th, Pole Vault
2012 NCAA Indoors - 17th, Pole Vault (All-America honorable mention)
2012 Pac-12 - 1st, Pole Vault (Pac-12 Champion)
2012 NCAA Prelims - 1st, Pole Vault
2012 NCAA Outdoors - 13th, Pole Vault (All-America Second Team)
2012 USA Jr. Champs - 5th, Pole Vault
2013 MPSF - 3rd, Pole Vault
Pole Vault.......17-10 1/4
Pole Vault.......17-8 1/4