"We went into the game at MetLife Stadium with a true freshman at quarterback," he said. "I think it was 104 degrees on the field throughout the game. We didn't have our best wide receiver [Allen Robinson] for the first half because of what I decided to do there. We put the defense into some tough situations. We did this with 65 scholarship players.
"We've got a very tough, resilient football team. Personally I'm going to try to do the best I can to improve this week as a head coach and do a better job offensively, defensively, and special teams. But to me, I just think we should be talking about [the positives] a lot."
Hackenberg threw for 278 yards and two touchdowns. Robinson, an all-Big Ten receiver last season, sat out one half because of an undisclosed disciplinary issue but wound up with seven catches, one for a score. Sam Ficken was perfect on all three of his field-goal attempts.
The running game, however, did not produce much. Zach Zwinak, a 1,000-yard rusher last season, managed just 61 yards in 24 carries. He had 4 yards in seven carries in the fourth quarter when the Lions were trying to run some clock.
After film study, O'Brien said, he felt the offensive line "blocked hard up front."
"I don't know why people think the offensive line struggled," he said. "When the play was called properly and the right players were put into the game, the offensive line blocked very, very well. We have a very good offensive line. The problem was the coaching. It starts with me. We've got to do a better job with the running game."
The coach hopes to see improvement for Saturday's home opener against Eastern Michigan at Beaver Stadium, but he's trying to keep everything in balance.
"We go through the whole film [Monday] and I show mistakes that they made and I certainly show mistakes that I made," he said. "Nobody in this program makes more mistakes than me. So I tell the guys that. That's important. I look to try to improve every single day, and I look to try to improve them every single day.
"But winning, winning, winning is the most important thing, and we won the football game. Winning is like salt water, it cures everything. Winning's the bottom line."
Contact Joe Juliano at firstname.lastname@example.org. Follow him on Twitter @JoeJulesInq.