Lehman, who missed a previous field-goal attempt and extra point, nailed his go-ahead kick with 2:50 left. It came after Wallace recovered a fumble at the Blue Hose 26 with just under five minutes remaining. Wallace's recovery came, in turn, after a 52-yard punt by Ayden Corrales left the Blue Hose at their 1-yard line.
Wallace's interception deep in Blue Hose territory with 15 seconds left clinched the win.
Dom Nankil threw a 7-yard touchdown pass to Josh Heverley early in the fourth quarter to give the Toreros (3-6, 3-3 Patriot League) a 13-13 tie after the PAT missed.
San Diego took advantage of a short field following a punt to score on Re-al Mitchell's 2-yard run to trail 13-7 at halftime.
Isaiah Williams rushed for 128 yards on 28 carries for San Diego.
Tyler Wesley threw for 153 yards with two interceptions for Presbyterian (3-6, 1-5). Jaden Wright had the only Blue Hose touchdown with an 18-yard run. It came after one of two lost fumbles by the Toreros. Mack Mikko kicked a pair of field goals.
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