The remaining ten men battled on for a point in the six goal thriller, but Crane was hit with a fine which Groves has installed for sending offs. It's a system that he believes has helped the Mariners good disciplinary record.
Groves told the Grimsby Telegraph of Crane's fine although he stated the red card was harsh. Groves then went on to point out Crane's potential after a shaky start.
"It's a standard fine," he told the paper. "We've got a system in place where, if players get sent off for whatever, then they get fined. It's a quite a severe fine and that's contributed to our disciplinary record.
"He's been punished for a sending off offence where he was a victim of the rules. It's not a dirty challenge and there isn't even any intent in there.
"He's still young and some things you have to learn from. He's been silly at times and got himself cautioned and he has to learn from that.
"We've had a number of chats. It's a case of him learning as he goes along. You have to remember that this is the first season where he's played consecutive games in the first team.
"I think he's shown a big improvement over the course of the season. We're still looking for him to continue that. He's still 21 and learning his trade.
"There's more to come from him but he's making progress in the right direction."