Robert Bortuzzo #41 of the St. Louis Blues passes the...

Robert Bortuzzo #41 of the St. Louis Blues passes the puck against the Vegas Golden Knights in the first period of their game at T-Mobile Arena on December 23, 2022 in Las Vegas, Nevada.  Credit: Getty Images

Necessity continues to force the Islanders to change their defense corps on the fly. Half of their original top six currently are sidelined.

They placed mainstay defenseman Ryan Pulock on injured reserve with a lower-body injury on Friday and simultaneously acquired 13-year veteran blueliner Robert Bortuzzo from the Blues for a seventh-round pick in 2024.

Bortuzzo is expected to be available when the Islanders continue their season-high six-game homestand against the Kings — who have won an NHL-record 11 straight road games to start the season — on Saturday night at UBS Arena.

Pulock did not play the final 8:14 of the Islanders’ 7-3 win over the visiting Blue Jackets on Thursday. He went down to the ice after blocking a hard shot from the left point by defenseman Zach Werenski off his right leg. Pulock, on IR retroactive to Thursday, is eligible to be activated next Thursday.

Defensemen Adam Pelech (long-term injured reserve/upper body) and Sebastian Aho (IR/upper body) already are absent, though Aho has resumed skating with the team and is eligible to be activated. Pelech can be activated off LTIR as soon as Dec. 19.

Journeyman Mike Reilly was claimed off waivers from the Panthers on Nov. 25 and has a goal and two assists in five games with the Islanders.

The righthanded Pulock, who has two goals and four assists while playing all 25 games, had been paired with rookie Samuel Bolduc the past four games.

Bolduc, with a secondary assist on the Islanders’ final goal on Thursday, notched his first point of the season. Bolduc’s ice time has steadily increased as his play improved while paired with Pulock. He logged 16:51 against the Blue Jackets.

“Probably just coming in every day and working hard and focusing on moving my feet and being more assertive,” Bolduc said. “Maybe confidence is more present, too, so it helps a lot.”

Bortuzzo, 34, is a righthanded shot like Pulock. He did not have a point in four games for the Blues this season.

Like Reilly, who played just two games for the Panthers before the Islanders claimed him off waivers, Bortuzzo will immediately get a chance to help his new team. He is in the second season of a two-year, $1.9 million deal.

Placing Pelech on LTIR allowed the Islanders, tight against the salary cap, to exceed the $83.5 million ceiling by Pelech’s $5.75 million cap hit.

The 6-4, 216-pound Bortuzzo has 20 goals and 54 assists in 537 NHL games.

Bortuzzo’s strength is as a stay-at-home defenseman. He skates well, if not fast, for his size and is a good penalty-killer.

Still, Pulock’s injury leaves the Islanders’ defense depth very thin past the top pair of Alexander Romanov and Noah Dobson.

The Islanders also will have to replace Pulock on the second power-play unit, where he’s played along the left wall to set up for one-timers.

Reilly is quarterbacking the second unit in Aho’s absence.

“I definitely feel comfortable up there,” Reilly said. “It matches my skill set.”

More Islanders

Newsday LogoSUBSCRIBEUnlimited Digital AccessOnly 25¢for 5 months