Balky back forces McDonagh out; Hayes missed trip

PITTSBURGH — It wouldn’t be wise to let Alain Vigneault call a coin flip for you right now.

After the Rangers coach said captain Ryan McDonagh was “a little bit more than 50-50” to play, the defenseman was forced out of Sunday night’s 5-2 loss the Penguins at PPG Paints Arena with back spasms.

McDonagh started suffering the spasms during the team’s 7-2 loss to the Islanders on Saturday afternoon at the Garden, when the defenseman was able to play 24:39. Vigneault said he considered McDonagh “day-to-day” and that “hopefully he’ll be all right for the next one,” which would be Tuesday at the Garden against the Flyers.

On Friday, Vigneault had also said center Kevin Hayes was “maybe less than 50-50” with his leg contusion before he was able to play against the Islanders. But that might have proved a bad decision, as Hayes was home in New York on Sunday to receive treatment.

“He felt fine [Saturday] before the game,” Vigneault said.

Hayes was hurt during the team’s final game before the five-day bye week, a 2-1 loss to the Golden Knights last Sunday, but spent the whole break getting treatment.

“During the game, he felt pain come back,” Vigneault said. “After [it], he just wasn’t feeling well. So we decided to keep him home and treat him and we’ll see how he’s doing [Monday].”

McDonagh was replaced in the lineup by Brendan Smith, who had been a healthy scratch for the previous two games. Smith might have played his best game in weeks, showing that physical edge that even boiled over in a second-period fight with Jamie Oleksiak.

That fracas started when Pittsburgh ruffian Ryan Reaves leveled Marc Staal, and then Smith leveled Reaves. Oleksiak apparently took issue with the two clean hits, and he was jumped Smith — getting a 10-minute misconduct and a two-minute instigator penalty.