Stanford’s offensive line is so beat up that the Cardinal moved defensive end Dylan Boles across the line of scrimmage this week, gave tight end Tucker Fisk reps on the line and added discus thrower Jake Koffman to the roster.

Even while starting three true freshmen, it was impossible to tell in Saturday’s 41-31 homecoming victory over Arizona on The Farm.

“Our young guys, God bless them. They just go hard,” Stanford head coach David Shaw said. “They make mistakes, and they come back and go hard. They’re never shy. They never back away. They take their coaching and try to get better.”

Led by junior center Drew Dalman and junior right tackle Foster Sarell, the Stanford offensive line didn’t allow a single sack and opened running lanes for 160 yards on 5.2 yards per carry.

Wait for it: Sophomore receiver Simi Fehoko had a breakout game with three catches for 97 yards and two touchdowns.

On the first, he streaked 44 yards and then contorted his body into the corner of the end zone. On the second, the 6-foot-4, 226-pounder simply outleaped a defender for a 14-yard touchdown that ended up being the game-winning score.

“This has been coming since the first time we saw him his sophomore year in Utah in high school,” Shaw said. “The young man is tall. He’s long. He’s got a sneaky stride. You don’t think he’s running as fast as he is, but he ran 4.3 for us in the spring. For a guy who is 6-3½ or 6-4, if you play underneath, he’s going to get over the top. If you’re up on him, he’s got a big-time vertical.”

K.J. Costello has seen this from Fehoko in practice for years, and the quarterback believes the game finally slowed down for his receiver. Fehoko agrees.

“I felt it today. It changed for me,” he said. “A lot during the season, I’ve felt that I’m rushed. I rush myself. But today, it finally slowed down.”

Triple duty: With kicker Jet Toner sidelined for the season with a leg injury he endured while covering a kickoff last weekend against UCLA, Ryan Sanborn handled punting, placekicking and kickoff duties.

The true freshman averaged 43.8 yards on five punts with excellent hang time and placement. He made all of his kicks (five extra points and field goals of 21 and 31 yards). Six of his eight kickoffs were touchbacks.

“He’s one of those rare guys who has the ability to do all three and to do them at a high level,” said Shaw, who is keeping Sanborn on a pitch count of sorts by monitoring the numbers of leg swings he takes during practice. “We don’t want him to do that at all times, but it looks like the rest of the year, he might have to handle that. He’s ready for it.”

Bye week: Stanford generally uses a bye week to rest the more experienced players and increase reps for the younger players. But since injuries have forced the Cardinal to play so many inexperienced players, everyone will rest this week. Shaw said the team will have only two short practices.

Rusty Simmons is a San Francisco Chronicle staff writer.