Illinois (1-3) was forced to use its final timeout with 11:15 remaining when it had the wrong personnel on the field. That proved crucial after John Gockman's 32-yard field goal pulled the Illini within seven points with 1:42 remaining.
Illinois recovered an onside kick and had a chance to tie. Forced to hurry, they got to the 4 before quarterback Jon Beujter was sacked on the game's final play.
Strang's return was just one of several big plays for Cal (2-3), which converted two key third-down plays during first-half scoring drives in building a 21-7 halftime lead.
Illinois coach Ron Turner tried to run out the clock in the first half, but the Illini were forced to punt with 45 seconds left. Strang caught the ball at the Cal 32 and ran right before reversing his field and sprinting down the sideline for the score.
Illinois jumped right back in the game when Beujter and Kelvin Hayden hooked up for a 72-yard touchdown on the first play from scrimmage in the second half.
The Illini stopped Cal's next drive and had momentum as the took over at their own 8. But a third-down interception by Brandon Sanders gave the Bears the ball at the Illini 26 and led to a 5-yard TD run by Adimchinobe Echemandu.
Cal quarterback Aaron Rodgers, making his first start of the season, completed 20-37 passes for 263 yards and one touchdown, a 14-yarder to Geoff McArthur hooked up six times for 90 yards in the second quarter.
Illinois marched 68 yards in14 plays on its opening drive, scoring when Beutjer his Halsey with a 10-yard pass to give the Illini a 7-0 lead.
Illinois' defense had Cal stopped in the next drive until Rodgers connected with McArthur on a 29-yard pass on third-and-21 to take the Bears to the Illini 26. The two hooked up for 19 more on the next play and. Two plays later, J.J. Arrington ran it from 5 yards out to tie the score with 3:31 to go in the first quarter.