This wasn’t concussion number one, or two, or three for Lubomir Visnovsky, but number six.

So it’s not a stretch to understand the concern the Islanders defenseman had before his return to the lineup in Monday night’s 6-3 loss to the Bruins at the Coliseum, ending a three-month absence.

“It was tough for me because after two months, I [was] not ready,” Visnovsky said Monday morning, a full week of practice under his belt since starting with the team last Sunday. “I’m not a young guy, and I was very frustrated. Right now, I’m very excited I’m back. We’ll see – I hope it will be OK.”

Visnovsky, 37, was hurt way back on Oct. 19, in the first period of the eighth game of the season.

Contrary to what was originally thought, Visnovsky wasn’t hurt on a hit from Hurricanes forward Radek Dvorak – a hit against the backboards after which he crumpled to the ice and left for the dressing room – but earlier in the game while his team was on the power play and forward Riley Nash got his arms up to finish a check near the blue line.

Because of his history, it didn’t take long for Visnovsky to recognize it was a concussion. His most recent one happened while he was playing for the Ducks on April 5, 2012, in the final game of the regular season against the Oilers. Before that, he said he suffered concussions, plural, while with the Kings from 2000-2008, and also one while playing for his hometown Slovakian team, Bratislava Slovan, during the full-season lockout of 2003-04.

“I know guys that have had eight, nine,” Visnovsky said, “and are still playing.”

But this one lingered longer than most, and that was especially upsetting for Visnovsky. On New Year’s Eve, he went to the University of Michigan to visit renowned concussion specialist, Dr. Jeffrey Scott Kutcher, the same doctor that had examined the Rangers’ Marc Staal, among other NHL players. Kutcher works with the Players’ Association and will be traveling to the Olympics in Sochi, Russia, to be the neurologist for Team USA.