SAN JOSE — The San Jose Sharks allowed a goal-ahead power play goal to Noah Cates early in the third period and were unable to get the equalizer in a 4-1 loss to the Philadelphia Flyers on Saturday.

With defenseman Mario Ferraro serving a roughing penalty, forward Christian Dvorak redirected a shot by Noah Cates past Sharks goalie Alex Nedeljkovic to give the Flyers the lead with 18:13 left in the third period.

The Sharks were unable to tie the game despite 10 shots on net in the third period, including five on a power-play opportunity, as they lost their fourth straight game.

Travis Sanheim and Noah Cates scored empty-net goals for the Flyers in the final 1:12 left of regulation time.

Dmitry Orlov scored the Sharks’ only goal at the 13:12 mark of the second period, as their record fell to 2-5-2 since a 7-5 home win over the Montreal Canadiens on March 3.

Ferraro got the roughing penalty after he went after Flyers winger Garnet Hathaway, who put a hard but clean shoulder-to-shoulder check on Macklin Celebrini in the corner to the left of the Sharks’ net. Ferraro got the only penalty on the play.

The game was a feisty one, with Barclay Goodrow having to fight Cates late in the second period. Cates went after Goodrow after the Sharks forward laid a heavy hit on Trevor Zegras. Ryan Reaves also fought Garrett Wilson in the first period.

The Sharks and Flyers entered the third period tied 1-1 after Orlov scored a power play goal at the 13:12 mark of the second period.

Macklin Celebrini carried the puck into the Flyers’ zone and dropped it back to William Eklund, who carried it toward the goal line before sending a pass in front to Orlov, who one-timed it past Flyers goalie Dan Vladar for his third goal of the season.

Right before the goal, the Sharks’ fourth line with Barclay Goodrow, Zack Ostapchuk, and Adam Gaudette set the tone with a heavy shift, perhaps helping to change the momentum.

Celebrini had been held without a point in the Sharks’ last two games: a 5-3 loss to the Edmonton Oilers on Tuesday and a 5-0 loss to the Buffalo Sabres on Thursday. In the 17 games this season in which Celebrini has been held without a point, the Sharks are 1-14-2 while being outscored 70-24.

Compounding matters for the Sharks has been that their second-leading scorer, Will Smith, had just two assists in his last eight games, and no points in his last five. Tyler Toffoli, San Jose’s third leading scorer, is out for an undetermined amount of time with a lower-body issue after he was injured during the first period on Thursday.

Sharks coach Ryan Warsofsky said before Saturday’s game that it remained unclear whether Toffoli would be able to travel with the team on Monday when they leave for Nashville to begin a three-game road trip. Toffoli, with 44 points in 67 games, sustained a lower-body injury during the first period of Thursday’s game against the Buffalo Sabres.

The Sharks play the Predators on Tuesday, the St. Louis Blues on Thursday, and the Columbus Blue Jackets on Saturday.

The Sharks on Saturday were also without defensemen Vincent Desharnais, who is considered day-to-day with an upper body injury.

Warsofsky said Desharnais’ injury is more the result of accumulation over time than any one incident. Desharnais also missed 23 games from late November to mid-January due to what he said was an elbow injury that required surgery.

Desharnais, when healthy, has been one of the Sharks’ top penalty-killing defensemen. In 10 games this month, Desharnais has averaged just under 21 minutes of ice time per game, and was the Sharks’ second-leading penalty killer (32:15) behind defenseman Mario Ferraro (34:18).

The Sharks right now are also dealing with injuries to No. 1 goalie Yaroslav Askarov (lower body), winger Igor Chernyshov (upper body), and center Ty Dellandrea (lower body).

The Sharks entered Saturday on a three-game losing streak and in 11th place in the Western Conference with 70 points, two points behind the Los Angeles Kings for the second wild-card spot. The Sharks were also one point behind both the Seattle Kraken and the Nashville Predators.