Updated

Indiana knows it must solve its defensive problems soon.

The 41-35 loss to Navy on Saturday showed the Hoosiers won't reach a bowl game unless their defense makes significant improvement. Navy compiled 515 yards of offense and had 444 yards rushing on its way to seven scores in nine possessions. Indiana's offense, despite five touchdowns on its final six series, couldn't keep up.

"I'm real disappointed," Indiana defensive coordinator Doug Mallory said. "You're not going to win many games if you let a team run for over 400 yards, never force the team to punt and create zero turnovers. Regardless of how good your offense is, you're not going to have a chance if you perform like that."

Improvement won't be easy. On Saturday, the Hoosiers face Bowling Green, a Mid-American Conference team that has played in a bowl game five times in the past decade and is averaging 37.5 points. The Falcons are 2-0 and had 576 yards of offense in a 41-22 victory over Kent State last week. Quarterback Matt Johnson has thrown for 508 yards and running back Travis Greene is averaging 5.1 yards per carry.

The Hoosiers have never faced Bowling Green.

"To me, it's a great opportunity," Indiana coach Kevin Wilson said. "We're going to play a very dynamic offense. We need to show what we're about. You'd like to stop them all the time. You're not going to. I'm expecting us to bounce back."

Stopping the run is the first priority. The Hoosiers (1-1) are allowing 5.3 yards per carry, a higher average than they yielded a season ago. Only six teams in the Football Bowl Subdivision are giving up more than Indiana's 287.5 rushing yards allowed per game. Navy's Keenan Reynolds powered through Indiana's defense for 127 yards on 32 carries, including three touchdown runs and a late fourth-down conversion that allowed the Midshipmen to run out the clock.

"Navy's a good team," Hoosiers cornerback Tim Bennett said. "Basically we need to get off blocks and play more physical. We've got to play harder. We're not going to get down over one game. We've got to take it in stride and learn from this."

Wilson is sticking by the Hoosiers' belief that they can have a quality defense without making drastic changes. But a lack of shuffling on Saturday caused consternation after Indiana's staff reviewed film.

Even as Navy consistently won battles at the line of scrimmage, the Hoosiers failed to retool their defensive line, which was manned primarily by ends Zack Shaw and Ryan Phillis and tackles Adarius Rayner and Ralph Green.

Reynolds also said after the game Saturday that he knew pretty much what to expect from Indiana on every snap.

"From a coaching standpoint, we did a bad job making adjustments," Mallory said. "We got stubborn. We continued to play it the way we practiced. There were some adjustments we had to make. We didn't."

Indiana's defense is a perennial concern among fans scarred by past experiences. In 2012, when the Hoosiers finished 4-8, they ranked 103rd out of 120 FBS schools in total defense, 101st in scoring defense, 98th in pass efficiency defense and 116th in rushing defense.

The Hoosiers thought more experience and an injection of freshman talent, such as starting middle linebacker T.J. Simmons, would help. By letting Reynolds and other Midshipmen run wild all night in Memorial Stadium, the Hoosiers showed they aren't quite there yet.

For now, Indiana doesn't plan to spend much time figuring out where it can alter schemes or personnel. Instead, Wilson wants players to maintain confidence, wipe away memories of the Navy debacle, improve fundamentals and try to create some turnovers.

"We just need to learn the way to win," Wilson said. "We're young. The learning is from game situations. You stay with the process. You start doubting, things don't work well."

Linebacker Flo Hardin said simply missing fewer tackles will go a long way. He's keeping the faith.

"Our defense, we all have thick skin," Hardin said. "We're all competitive. We don't like losing. You can't dwell in the past and let Bowling Green beat us because we're thinking about the loss against Navy. We can't let one game kill our whole season."