The Tigers (2-0) scored three times in the second half after the Spartans (1-1) took a 10-7 lead into halftime. Auburn struggled to hold off the more than
The onside kick went out of bounds untouched to end the threat, even if it wasn't pretty.
"Coach (Bryan) Harsin just talked about it," said Finley, who started again at quarterback. "We easily could have lost this game.
"To go out there and find a way to get the job done, that's all that matters. It doesn't matter how much we won by."
The Tigers couldn't feel at all comfortable until Finley barreled in for a 4-yard touchdown and a 24-13 lead early in the fourth. He set it up with a 24-yard pass to Ja'Varrius Johnson.
But Auburn's platooning of quarterbacks Finley and Ashford continued to produce inconsistent results - and an interception apiece.
Finley completed 13 of 20 passes for 167 yards. Ashford's three atttempts netted only a 1-yard completion but he did run for a 30-yard gain and 61 yards.
Auburn has won two straight after ending last season on a five-game skid.
"Just to finish and play well enough in the second half to win. We didn't do that at times on last year's team," Harsin said. "So that was something that we emphasized from January and we emphasized all through fall camp."
Auburn's first two touchdown drives were kept alive by fourth-down conversions, including one where Finley salvaged a botched snap. He dropped the ball, picked it up and hit Bigsby in the flat for an 11-yarder.
Bigsby then plunged into the end zone for a 1-yard score early in the third quarter.
Spartans coach Brent Brennan was trying to pull off another SEC upset. San Jose State beat Arkansas 31-24 in 2019 in his only other attempt.
"It was awesome to see how they responded to the ups and downs," Brennan said. "I thought they did a great job, just handling that and not listening to the haters and the naysayers, and coming down here and playing a heck of a football game."
San Jose State went into the locker room with a halftime lead thanks to Kairee Robinson's 1-yard touchdown in the final minute.
Hunter had scored on a 7-yarder for Auburn. Finley made a halftime promise to his teammates.
"I was like, 'Guys, I've got y'all. I'm not going to make any more mistakes and we're going to win this game,'" Finley, who completed 12 of 15 passes after his interception, said. "I meant that from the bottom of my heart."
San Jose State: Had a few chances to strengthen its upset bid, missing a field goal and having to settle for three points after first and goal from 1 thanks to back to back false start penalties.
Auburn: Didn't seem to resolve the quarterback situation with much tougher opponents looming, with Ashford serving mostly as the runner and Finley the passer. But the defense did hold off San Jose State until the offense got going some in the second half.
CARLSON MOVES UP
Auburn kicker Anders Carlson moved past Wes Byrum into second place on Auburn's scoring charts, with 364. His older brother, Daniel, holds the record with 480.
San Jose State hosts Western Michigan on Sept. 24 after an open date.
Auburn hosts Penn State next Saturday in its first major test.