Tough way to learn a lesson.

The Maple Leafs didn’t lose on a power-play goal in overtime against the Buffalo Sabres on Friday night, but the punch to the gut in the extra session certainly felt like they had.

Defenceman Paul Ranger, who held the non-dangerous Ville Leino as the Sabres forward skated behind the Leafs net late in the third period, barely was back on the ice after serving a minor when Christian Ehrhoff’s shot got past James Reimer.

“It was a blatant hold by our defenceman,” Leafs coach Randy Carlyle said. “It’s new rules hockey.”

Ranger declined to comment after the game, so we weren’t able to learn why Leino, who has no goals and five assists in 15 games, was such trouble to contain.

As for special teams, the Leafs gave up one power-play goal on four Sabres opportunities, while failing to score on their only man advantage. The once-vaunted Leafs penalty kill had fallen to 20th in the National Hockey League heading into Friday’s games.

“That’s what makes the difference in hockey games, the difference in losing some and winning some — special teams did a great job tonight,” Sabres coach Ted Nolan said.

“We talked about it. Toronto has the second-best power play in the league. If we weren’t disciplined tonight, if you give (Phil) Kessel a few chances on the power play, he is going to put it in.”

The Leafs, clipping along with a 4-5-3 record in November, were getting wins mostly because of excellent goaltending and sharp special teams performances. Now, they’re not really getting either.