Second-line center Kevin Hayes (abdominal) reinjured himself in the Flyers’ game against the Calgary Flames on Nov. 16 and is now considered “week to week,” coach Alain Vigneault said after practice on Monday. He did not have a specific timeline for Hayes’ return.

Hayes made the trip to Tampa Bay with the team in advance of Tuesday night’s game against the Lightning. He is expected to stay in Tampa for a couple of extra days to receive treatment from a specialist identified by the Flyers’ medical staff.

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“We have a couple of opinions,” Vigneault said. “So at this time, all I can say is he’s week to week. Reinjured the same injury and we’re in the process of rehabbing there.”

In the second period against the Flames, Hayes got tangled up with Flames forward Elias Lindholm and fell to the ice before scrambling off to the locker room. Hayes missed the rest of the second period, but he returned for the third and finished the game with 14 minutes and 51 seconds of ice time. Additionally, Hayes participated in practice with the Flyers the following day and even made a brief appearance at morning skate before being ruled out of their game against the Tampa Bay Lightning on Nov. 18.

Hayes had abdominal surgery on Sept. 21 and started the season on long-term injured reserve. After sitting out for the first 12 games of the season, he made his return to the lineup on Nov. 13 against the Dallas Stars. In total, Hayes played two games and scored his first goal of the season against the Flames before he was sidelined again with injury.

With Hayes out for the time being, the Flyers recalled Max Willman from the Lehigh Valley Phantoms on Nov. 18. Willman is expected to be in the lineup against the Lightning.

Still looking for an offensive spark

Over the last 10 games, the Flyers have struggled to score, registering just 18 goals while allowing 27. In an effort to do away with the recent trend, Vigneault tried shaking up the Flyers’ forward lines and power-play units in practice on Monday afternoon.

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Vigneault’s adjustments to the forward lines focused on the bottom six, with Willman and winger Oskar Lindblom trading places — Willman skated on the third line with center Scott Laughton and winger James van Riemsdyk, and Lindblom skated on the fourth line with center Nate Thompson and winger Zack MacEwen.

However, those tweaks to the lines aren’t guaranteed to survive until Tuesday night’s game.

“I wanted to see it in practice today just to take a look at it,” Vigneault said. “Gonna sit down with my assistants later on today and decide what the lineup is going to be.”

Vigneault also introduced a new face to the second power-play unit: defenseman Travis Sanheim. He was positioned on the left side of the formation with defenseman Keith Yandle at the point, center Sean Couturier on the right side, winger Joel Farabee in the slot and van Riemsdyk as the net-front presence.

Against the Bruins on Nov. 20, Vigneault tried Lindblom in the slot on the second power-play unit. However, Vigneault decided that utilizing Lindblom on both the power play and the penalty kill was too challenging of a workload in addition to his five-on-five duties.

“We’ve played Travis on one of the power-play units in the past,” Vigneault said. “Had him out there today. Hopefully, he can bring something tomorrow and he can help us win that game.”

The Flyers’ top power play from the game against the Bruins — winger Claude Giroux on the left, defenseman Ivan Provorov at the point, winger Cam Atkinson on the right, center Derick Brassard in the slot and winger Travis Konecny at net-front — remained intact in practice on Monday. With this personnel, Brassard scored a power-play goal against the Bruins, the team’s first since Nov. 13 against the Stars when Provorov found the back of the net.