The Gophers are heading into their biggest nonconference test of the season, at Texas Christian, knowing quarterback Mitch Leidner's status is in doubt.

Leidner has a sprained medial collateral ligament in his left knee, sources familiar with the injury confirmed Sunday.

The good news for the Gophers is it's not a torn anterior cruciate ligament, an injury that already has ended the season for tight end Duke Anyanwu and defensive tackle Scott Ekpe.

The bad news is that Leidner could still be sidelined for multiple weeks, perhaps into the start of Big Ten play, depending on the injury's severity.

"Any time you have a knee [injury], you're concerned," coach Jerry Kill said Sunday, while awaiting an update from the medical staff. "We haven't had a lot of good luck [with recent knee injuries]."

Kill said he might not give an update on Leidner's status until Thursday, when the team releases its official injury report and depth chart.

If Leidner can't play at TCU, the Gophers would turn to Chris Streveler, a redshirt freshman who has thrown one college pass. Kill said Jacques Perra, a walk-on from Roseville, has climbed to No. 3 on the depth chart.

"We're trying to redshirt [Perra]," Kill said. "If it was today, that's what we'd do because we're trying to redshirt Dimonic [Roden-McKinzy], and Jacques had a great camp, and throws the ball very well and does a good job."

The Gophers led Middle Tennessee State 35-17 when Leidner got injured early in the fourth quarter Saturday. He had just released a third-down pass to KJ Maye, when he got hit on the knee by linebacker Leighton Gasque, causing his left leg to buckle.

Team doctor Pat Smith tested Leidner for ligament damage, and trainers placed a brace on the knee. Leidner ran OK along the sideline but had difficulty replicating his drop-back motion, a clue that the damage was to the lateral ligament.

Leidner had an MRI exam, but there has been no word on the severity of the sprain. According to WebMD.com, there are three grades of MCL sprains: Grade 1, which heal in one to three weeks; Grade 2, which heal in about a month; and Grade 3, which could take four to six weeks.

If it's three weeks, Leidner could miss TCU, San Jose State and the Big Ten opener at Michigan. After that, the Gophers have a bye week before facing Northwestern (Oct. 11) and Purdue (Oct. 18).

Leidner has been the team's primary leader since Philip Nelson announced in January that he was transferring, so the Gophers would surely miss the sophomore's 6-4, 237-pound presence on the field. But a cynic would say others could surely better his passing numbers from Saturday — 5-for-11 for 67 yards, with one touchdown and one interception.

The Gophers fully expect Leidner to blossom over time. He had some good moments in the first two games, but they rank second-to-last in Big Ten passing offense, at 111.5 yards per game.

Leidner has completed 50 percent of his passes (14-for-28). He was a bigger threat to run last season, but trying to keep him healthy, the Gophers limited him to 12 carries in two games.

Streveler is more of a pure runner than Leidner and has far less zip on his passes. Streveler tore a tendon in his right thumb last season, requiring surgery, and the Gophers were concerned he might need to move to wide receiver.

But Streveler made a full recovery and has held down the No. 2 quarterback spot, behind Leidner. Streveler racked up 48 touchdowns — 26 passing and 22 rushing — as a senior at Marian Central Catholic in Illinois. He was known for his accuracy, completing 68.8 percent of his passes.

This season, Streveler played the final two series against Eastern Illinois and the final two series against Middle Tennessee. He completed his only pass — a 12-yard strike to tight end Brandon Lingen — and has rushed six times for 23 yards.

"We believe in him," running back David Cobb told 830-AM on Sunday. "If Strev's the guy we have to go with, we'll be behind him 100 percent."

Joe Christensen • jchristensen@startribune.com