Garza was benched midway in the first quarter after fumbling twice, although both were recovered by St. Francis.
But the tough-to-tackle 5-7, 155-pounder returned to gain 154 yards on 23 second-half carries, and scored the game-winning touchdown on a five-yard run with 55 seconds remaining in the 14-7 victory.
The three-time defending City League champions have now won nine of the last 12 meetings in this heated rivalry, and Garza's late score enabled St. Francis (5-1, 3-0 CL) to win for the third straight week on its final drive.
"I was really disappointed in myself," said Garza, who totaled 180 yards on 28 rushes.
"I hadn't really fumbled the ball this year and, in the biggest game of the year for St. Francis, I come out and do that.
St. Francis defender Brandon Kulka tries to strip the ball from St. John's running back Rusty Marvin in the Glass Bowl.
wadsworth / Blade Enlarge
"I got down on myself, but my coaches and my team picked me up. I knew the second half had to be way different, and we all went out and played our hearts out."
Two weeks ago Garza scored with two minutes to play, capping a 95-yard Knight drive in a 17-14 win at Clay. Last week, senior quarterback Brandon Speweik bolted 44 yards for a TD with 1:13 left in a 12-7 win at Whitmer.
"You play hard for the whole 48 minutes," Knights coach Dick Cromwell said. "You never know when a big play is going to [happen], whether it's the opening kickoff or the last play of the game. We try to preach that, and the last three weeks it's taken us right to the last play."
This time, the Knights, who got the ball back with 3:55 to play, covered 63 yards on 10 plays (all runs) to gain the victory.
Garza ran eight of those for 45 yards, and scored on a surge over left guard on a second-and-1 play.
Speweik contributed runs of 11 and 7 yards during the winning march.
"We're going to give coach Cromwell a heart attack if we keep doing this," Garza said. "But I guess that's how it is sometimes. Win by a point, or win with three seconds left. A win's a win."
St. John's (3-3, 2-1) struggled offensively throughout, but used two big plays and some trickery to tie the game 7-7 with 8:33 left.
On third-and-8 from his 20, senior Titan QB Andrew Vollmar found receiver Blake Haudan for a 55-yard completion.
After a 13-yard burst from backup tailback Rusty Marvin gave St. John's a first down at the 12, a sack and two Titan penalties created a third-and-29 situation.
Vollmar hit Marvin on a 26-yard screen pass to the left, and the Titans scored on fourth down from the 5 on a reverse pass.
Backup QB Sean Patterson rolled left, pitched on the reverse to Vollmar, who hit Haudan for the TD.
In a game that was scoreless after three quarters, the Knights broke the ice on the first play of the fourth.
They capped an 11-play, 79-yard drive on a three-yard TD pass from Speweik to tight end Jon Sheehan.
St. Francis rushed 50 times for 258 yards. Speweik was 2-of-5 passing for 15 yards.
St. John's was held to 71 yards on 29 rushes, with tailback Dorian Milletti (12 carries, 42 yards) and fullback Marcus Waugh (7 carries, 21 yards) held in check. The Titans were also saddled by 11 penalties totaling 117 yards.
"There were times we didn't block a soul up front, and you've got to be able to run the football," Titans coach Doug Pearson said. "Other than the long pass to Haudan, we didn't move the ball. I'm really disappointed.
"They're a good football team and they always play great defense. It's back to the drawing board. This is the same spot we were in last year."
Vollmar (4-of-10 passing, 87 yards) was intercepted at midfield with 41 seconds remaining by Jim Paszczykowski, icing things for the Knights.
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