The NHL has a clear message to coaches starting this season: Don’t challenge an offside call unless you are really, really sure.

At times last season, coaches challenged on the off chance a goal would get called back or to at least give players a breather because all it cost was a timeout. That is expected to change because, pending approval from the board of governors Wednesday, a failed offside challenge will instead result in a penalty as the league tries to get the coach’s challenge closer to what it was intended to be.

Commissioner Gary Bettman said that last season, the second with coach’s challenges for offside and goaltender interference, included an increase in the total number of reviews and the percentage that were not overturned.

“We’re in effect trying to discourage using the coach’s challenge on offside unless you’re really 100 percent certain that you’re going to win because it was a blown call,” Bettman said. “The coach’s challenge was really intended to focus on glaring errors. And by imposing a two-minute penalty if you’re wrong, it should limit the number of challenges to those instances where there’s a glaring error.”

It’s still not perfect because a coach who wants to take a chance can still claim goalie interference in some instances. And there’s still the concern that challenges take too long to figure out, but the league hopes fewer unneeded reviews make for a positive step forward.

Here are some other rule changes or points of emphasis this season:

NO TIMEOUT AFTER ICING

Since 2005, teams have been unable to make line changes after icing the puck, with the design of creating some extra offense from fatigue. Coaches got around the rule by calling timeout to provide players some extra rest, but now that won’t be allowed.

“That’s consistent with the original intent of the icing rule that there was to be no substitution by the team that iced the puck,”…