BOSTON – The Islanders can take a lead. They just can’t keep a lead. And, to paraphrase noted philosopher Jerry Seinfeld, that’s really the most important part of taking a lead.

The Islanders mishandled a two-goal lead for the second straight time to start this four-game road trip, losing, 5-2, to the struggling Bruins on Tuesday night at TD Garden.

The Islanders (4-4-1) also scored the first two goals in Saturday’s 4-3 shootout loss to the Flyers.

This time, they went 0-for-5 on the power play, failing to capitalize on a four-minute advantage that ended the second period and started the third.

The Bruins (5-7-0), who entered the match in a 1-7-0 skid, meanwhile were 2-of-4 as Ilya Sorokin (17 saves) gave up four or more goals for the fifth time in seven starts.

Tuesday’s match was a special one for rookie defenseman Marshall Warren of Laurel Hollow, playing in his second NHL game after his two-assist debut in Philadelphia as it marked the first time his father, Lewis, was able to see him play for the Islanders in person. He missed Saturday’s match to be with Marshall Warren’s grandfather, who remains hospitalized.

“My dad’s coming up so I’m pumped for that and it’s his birthday today, too,” said Warren, who grew up an Islanders’ fan. “It’s kind of weird how God works. I’m really pumped to see him after the game and just give him a hug. I miss him.”

But Warren’s first NHL penalty, a tripping call against Mark Kastelic, led to Elias Lindholm’s power-play goal at the net at 3:57 of the second period to bring the Bruins within 2-1.

David Pastrnak, from low in the right circle, tied it at 6:49 and Mikey Eyssimont gave the Bruins a 3-2 lead by getting to the crease and redirecting Charlie McAvoy’s feed. The Long Beach defenseman made it three Long Islanders in the match,, along with Smithtown’s Kyle Palmieri.

Morgan Geekie, with his sixth goal in five games, added a second power-play goal to make it 4-2 at 5:48 of the third period.

The Bruins held an 11-1 shot advantage at one point in the second period.

This after coming off Monday night’s 7-2 loss in Ottawa, after which rookie coach Marco Sturm criticized his team for not buying in.

But the Islanders scored twice in the opening 4:32 of the first period. Bo Horvat connected off the rush on the Islanders’ first shot against a difference-making Joonas Korpisalo (33 saves) at 1:08 and Palmieri was open low in the right circle for Mathew Barzal’s feed at 4:52 on a delayed tripping call against defenseman Nikita Zadorov.

Notes & quotes: Defenseman Alexander Romanov (upper body/injured reserve) participated in the morning skate, but coach Patrick Roy said there was no update on his timeline to return. Romanov missed his fifth game and is eligible to be activated. “We’ll see how he feels when he gets more contact,” Roy said…Rookie forward Max Shabanov (upper body) missed his third game and is not traveling with the team…Defenseman Adam Boqvist was the healthy scratch.

Andrew Gross

Andrew Gross joined Newsday in 2018 to cover the Islanders. He began reporting on the NHL in 2003 and has previously covered the Rangers and Devils. Other assignments have included the Jets, St. John’s and MLB.