The Flyers, off to a 3-1 start despite some uneven play and a rash of injuries, face their first road test of the young season Thursday in Boston.

“It’s a good sign,” captain Claude Giroux said about the Flyers’ record as they still search for cohesiveness, “and we know we can play better.”

They have been outshot in all four games and have had numerous defensive breakdowns. Still, 3-1 is 3-1 — their best start since going 3-0-1 to begin the 2011-12 season — and they are coming off a workmanlike 3-0 win over improved Buffalo.

“Probably our best effort of the season,” Giroux said.

The Flyers, who played their first four games at the Wells Fargo Center, will face the Bruins (1-1-1) Thursday and Saturday, then head to Newark and meet surprising New Jersey (2-1) twice. Thursday’s game will be Boston’s home opener.

The Flyers are already without star center Sean Couturier, who is expected to miss at least two weeks with a rib injury, and they could be missing his replacement, Morgan Frost, and defenseman Phil Myers. The latter two players suffered undisclosed injuries in Tuesday’s win over the Sabres and were scheduled to have MRI exams on Wednesday. The Flyers did not have a medical update Wednesday.

If Frost can’t play Thursday, Connor Bunnaman is expected to crack the lineup and could be at center. Another option: Moving Giroux from wing to center, his natural position, and playing Bunnaman or Samuel Morin at wing. Bunnaman in on the 23-man roster, while Morin is on the taxi squad. (With Myers and Shayne Gostisbehere perhaps out for a while, it’s worth wondering whether the Flyers will put the physical Morin back on defense.)

Frost appeared to injure his left arm or wrist after taking a hit behind the net from Buffalo defenseman Jake McCabe. Myers also left the game after a McCabe hit. Both hits were clean.

If Myers is sidelined, right-handed shooting Mark Friedman figures to be in the defensive rotation. Friedman, 25, a third-round draft pick in 2014, played most of last season with the AHL’s Phantoms and had six games with the Flyers.

Gostisbehere would have been the Flyers’ first option to join the defense, but he is on the NHL’s COVID-19 protocol list.

The Flyers have allowed 34, 33, 36, and 40 shots, respectively, in their four games. Last year, in a 69-game season, they allowed 30 or more shots in four straight games just once.

Thus far, the Flyers have had just 42.7% of the five-on-five shot attempts.

Goalies Carter Hart and Brian Elliott have masked the defensive shortcomings and turnovers, keying the 3-1 start.

In Tuesday’s win, Elliott made 40 saves and the new No. 1 defensive pairing of Ivan Provorov and Travis Sanheim played well. Provorov blocked a shot that probably saved a goal during a five-on-three Buffalo power play. He finished with five blocks, three hits, and a plus-2 rating in 27:02, while Sanheim had four hits and a plus-1 rating in 25:13.

The Flyers outhit the Sabres, 38-17. Leading the way was Travis Konecny, who had six hits, was at his chirping best, and scored what turned out to be the winning goal on a clever backhand shot on a breakaway late in the second period.

“They weren’t perfect out there,” Alain Vigneault said of his players. “[Buffalo] obviously had some good looks. “But as far as competing, working hard and trying to play the right way, this was our best game so far and we have to continue to get better.”

The Flyers will meet a Bruins team that is coming off a 1-0 loss to the Islanders and hasn’t scored a five-on-five goal in its three games. Boston is without star right winger David Pastrnak, who had offseason hip surgery and is expected to be sidelined a few more weeks.

“We have confidence in our group,” Boston forward Jake DeBrusk told reporters after Monday’s loss. “I think we’re really stacked up front.”

Those Bruins forwards will try to exploit a shorthanded defense that is still seeking an identity.