Auburn freshman Stanley Floyd, who will be 19 Monday, celebrated early by winning the 100-meter dash at the U.S. Olympic Track and Field Trials today.

Floyd, clocked in 10.26 over a rainsoaked track, defeated his mentor, 1976 Olympian Harvey Glance, who finished second in 10.27. Floyd was winning his 12th straight 100-meter final, including NCAA and Athletics Congress titles.

Willie Banks won tonight's other final, the triple jump, at 55-1 1/2 as the weather sharply limited the performances.

Renaldo Nehemiah advanced to Monday's semifinals in the 110-meter high hurdles, breezing through two rounds in 13.55 and 13.56. Nehemiah's D.C. International teammate, Greg Robertson, also advanced. Greg Foster, after wining his first heat, withdrew with tonsillitis.

James DeRienzo of Georgetown qualified for the 800-meter final in 1:46.85, as Mark Belger and Evans White were eliminated.

Edwin Moses ran the year's fastest time, 48.22, to gain the 400-meter hurdles final. Mike Shine, the Olympic silver medalist, and Maryland's Chris Person were also-rans.

Madeline Manning, the 1968 Olympic champion, won her 800-meter semifinal in 2:03.24. Washington D.C. product Robin Campbell took the other semi in 2:03.92, with Georgetown's Chris Mullen a nonqualifying fifth. o

Paul Girven and Jalene Chase of Maryland qualified for the women's high jump final.