A win would have given UCI (30-12, 9-5), ranked No. 17 by the National Collegiate Baseball Writers' Assn., a four-game lead in the loss column over the Mustangs. The top two teams from the Big West figure to earn berths into the NCAA regionals.
The loss also washed away what would have been sophomore left-hander Matt Whitehouse's third win in his last three starts. Whitehouse, who has emerged as a second ace behind Friday starter Matt Summers, arguably deserved nothing less than a victory. He struck out eight and walked none while allowing seven hits and two earned runs in 7 2/3 innings. He has now surrendered just three earned runs in his last four starts, during which he has worked 25 1/3 innings. That's a 1.07 earned-run average to lower his season ERA to 1.69.
Whitehouse had thrown 107 pitches when he was relieved by Hernandez after a two-out double in the eighth. Hernandez was greeted by an RBI single from Denver Chavez, but retired the side to preserve a 3-2 lead.
Hernandez, who entered with nine saves and three wins in as many decisions, walked the leadoff man in the ninth.
Cal Poly's J.J. Thompson launched the next pitch high into the hazy sky toward left and UCI left fielder Scott Gottschling ran out of room as he ventured to the foul pole, where the ball sailed out of the park.
Home play umpire Dan Ignosci continued walking up the third-base line, then put both hands up while looking at one base umpire, who was positioned near second base. Ignosci did not immediately gesture fair or foul and he appeared to be asking for help, as if he had lost sight of the would-be homer.
The foul call, later deemed erroneous by UCI third baseman Drew Hillman and catcher Ronnie Shaeffer, triggered a heated argument from Cal Poly Coach Larry Lee, a former Orange Coast College player who viewed the play from the third-base coaching box.