USF has offset a low-scoring offense with stingy defense much of the season. Against rival Santa Clara on Thursday night, even that wasn’t enough. Held to 19 points in the first half, the Dons spent the second half trying to claw back but fell 65-62 to the Broncos on the Hilltop. The Broncos, who came into the game as the lowest-scoring team in the WCC, shot 50 percent from the field and went 8-for-10 from the foul line in the final 1:07 to seal the victory. Down by as many as 10 early in the second half, USF had several chances to close the gap. Guard Frankie Ferrari’s layup off a turnover cut the Dons’ deficit to 46-43 with just less than nine minutes left.