Gophers coach Jerry Kill knew there'd be growing pains at quarterback this season with a sophomore starter (Philip Nelson) and a redshirt freshman backup (Mitch Leidner).

Developing quarterbacks takes patience, so Kill wasn't ready to replace Nelson as the starter, just because Leidner had played well with Nelson out because of a hamstring injury.

And despite some fans' pleas, Kill decided not to pull Nelson, even for one snap, during Saturday's 23-7 loss to Iowa.

"Philip was our first-team quarterback, and he played well until he got hurt," Kill said Sunday. "And then we have the guy who's his backup [Leidner] come in, and he does a good job, gets us some wins. But Philip comes back, and he's healthy and ready to go. So we play him, and I get all these quarterback questions. That kind of amazes me."

Nelson has made 11 starts for the Gophers. In the game before he strained his right hamstring, at New Mexico State, he completed eight of 15 passes and rushed for 122 yards.

When Nelson got hurt against Western Illinois, Leidner came in and completed seven of eight passes, an accurate showing for a team that has completed only 52 percent of its passes this season.

One week later, Leidner completed only five of 12 passes but rushed for 151 yards and four touchdowns against San Jose State, earning Big Ten Freshman of the Week honors. But Kill trusted Nelson to tell him when his hamstring was ready to play, without limitations.

"A guy loses his job if the other guy's playing three times better than he was when he got hurt," Kill said, making it clear that hadn't happened in this case.

Nelson did not play well against Iowa. He completed 12 of 24 passes for 135 yards and one touchdown with two interceptions. He also rushed nine times for minus-18 yards, including four sacks. He missed a few key passes, including a third-down post route to Derrick Engel that could have pulled the Gophers within 20-14 with 10 minutes remaining.

But as a team, the Gophers rushed 27 times for only 30 yards. Those numbers would make it hard for any quarterback.

"Was [Nelson] the total reason we played poorly? I don't think so; I think it's a team game," Kill said. "And did he miss a couple shots down the field that maybe he'd like to have? Yeah, certainly. But there are 10 other guys that have to execute, and 11 others on defense."

Kill did say the coaching staff strongly considered inserting Leidner for a series to "change the rhythm."

"But if you just start pulling people because they're not playing well, then you've got everybody losing confidence," Kill said.

On Saturday, it sounded as if they decided against it because they knew they'd have to throw the ball and felt Nelson was the more reliable passer. On Sunday, Kill clarified, saying the decision to stick with Nelson "doesn't mean Mitch can't throw because Mitch throws it well."

But factoring in the time-of-possession difference — Iowa 36:01, Gophers 23:59 — Kill said, "We didn't have time to [let Leidner get acclimated], so we felt having [Nelson] being in there gave us the best chance."

Of course, Kill knows that explanation might not appease fans, who wanted him to pull out every stop against Iowa.

"Maybe Mitch would have gone in there and changed the whole game and lit it up, I don't know," Kill said. "But that's the decision we make. Whether it's right or wrong, that's what we get paid to do, and I guess it wasn't right [Saturday]."

If Nelson struggles again this week at Michigan, perhaps then it will be Leidner's turn again. The Gophers will be at the halfway point of their season with a bye week to prepare for their next game, at Northwestern.

But any decision would be made carefully, knowing the long-term impact it could have on both quarterbacks' development.

"We don't have a big quarterback controversy," Kill said. "We've got a darn sophomore quarterback [Nelson] and a freshman [Leidner], and they're both good players, and they're both learning on the job a little bit. So that's where we're at with all that."

Joe Christensen joe.christensen@startribune.com