Junior first baseman Connor Spencer was four for four with three runs batted in to lead the host Anteaters, who swept the three-game Big West Conference series that concluded Sunday.
UCI (24-11, 8-1 in the Big West) remained tied atop the conference with Cal Poly San Luis Obispo. The Anteaters also earned the No. 21 ranking in the Collegiate Baseball poll.
UCI starter Evan Brock earned the win and is now 6-2.
Chris Rabago was two for four with two RBIs while Grant Palmer and Jerry McClanahan both had two hits and one RBI to contribute to the 'Eaters' 14-hit attack.
Cal State Northridge fell to 13-22, 2-7.
Vanguard settled for the split, as the Lions won the first game, 10-2, but then lost, 4-1, in Golden State Athletic Conference action Tuesday at Vanguard.
Taylor Wilson was one for two with three runs batted in for the Lions (30-20, 10-10 in conference) in the win, when Breanne Gomez went two for two with one RBI and brittany Colenzo went two for two with two RBIs and two runs scroed.
Shelby Kuryllo led Vanguard at the plate going two for three to close out the doublheader.
Orange Coast 8, Fullerton 5
Briana Magdaleno went four for four with two home runs and five runs batted in to lead the host Pirates to their third straight win at home in the Orange Empire Conference game Monday.
Katie Kendrick added two hits for OCC (9-19, 4-14 in conference).
Kellie Tiner struck out 10 to earn her ninth win of the season and drop Fullerton to 19-18, 6-12.