Sure, it was tense. But after giving up some big plays - and 33 points - to Indiana, the University of Michigan football team made two crucial fourth-quarter defensive plays and held on for a 36-33 victory.

All’s well that ends well, right?

Not exactly. The Wolverines entered Saturday’s game sixth-best in the Big Ten in points allowed (58), and have given up an average of 20 first-half points in the last three games - a trend Michigan defensive players agree must end if the Wolverines (4-0) are going to continue winning.

“A lot of these performances from the defense haven’t been acceptable,” sophomore defensive tackle Ryan Van Bergen said. “They’ve won us games, but they’re not what we’re striving for.”

Van Bergen made a key fourth-quarter sack that helped Michigan get the ball back for the eventual game-winning touchdown.

But just a few minutes earlier, Van Bergen missed a check that led to an 85-yard touchdown run by Indiana’s Darius Willis - the longest run Michigan has allowed since 1987 - that gave Indiana a 33-29 lead.

“I made the wrong check,” Van Bergen said. “It doesn’t happen very often, but I did it, and it was independently on me, and it almost cost the team a big loss. I would have blamed that completely on myself.”

Van Bergen, though, was hardly of author of Michigan’s lone defensive breakdown. The Wolverines allowed 467 yards to a team that isn’t known for fielding a superior offensive unit. That’s partly, defensive coordinator Greg Robinson said, because Indiana’s offense showed new looks.

“They came out with a lot of things we hadn’t seen, and we had to get a feel for things,” Robinson said.

Coach Rich Rodriguez encouraged people to show patience toward what remains a young Michigan defense.

“We have to remember there are a lot of first-year starters playing defensively,” Rodriguez said. “Some guys are getting some reps for the first time, and we only had two seniors, so we’re pretty inexperienced.”

Senior linebacker Stevie Brown, though, said lack of experience isn’t an excuse - players must know where they’re supposed to be on the field.

“We’ve got to make sure we’ve got proper communication,” Brown said. “When we don’t have the right communication, and people start doing different things, that’s what happens.

“I can’t pinpoint (breakdowns) - I just know it’s a lack of communication, because every time we come off to the sideline after a big play happened, it’s like, ‘What happened?’ And some people are like, ‘Well, I thought we were playing this,’ and some people are like, ‘I thought we was playing this.’ So, if we can just communicate and keep people on the same page, we’ll be fine.”

Most of the mistakes, Van Bergen said, are related to fundamentals - “tackling, assignment football, being ready for different kinds of motions” - and, most importantly, are correctable.

“If we can be ready for some of the things you can throw at a young defense to try and throw them off, we’ll keep getting better,” Van Bergen said.

James Briggs covers sports for AnnArbor.com. Contact him at 734-623-2557 or jamesbriggs@annarbor.com.