Auston Matthews will miss his second straight game Tuesday as the Toronto Maple Leafs take on Philadelphia Flyers.

Matthews, who skated Tuesday morning, missed Sunday's game against the New York Islanders with an undisclosed injury. 

The Maple Leafs will also be without defenceman Jake Muzzin on Tuesday, as he misses his third straight game. Both Muzzin and Matthews will, however, accompany the Leafs on their coming three-game road trip beginning Thursday in Tampa.

Matthews, a native of Scottsdale, Ariz., is currently two goals shy of reaching the 60-goal plateau for the first time and is four goals ahead of Edmonton Oilers forward Leon Draisaitl for the Maurice (Rocket) Richard Trophy lead.

"It's just not worth him having to play through anything, as minor as it might've been," head coach Sheldon Keefe said Sunday of Matthews. "We got to be smart with those kind of things. If it was a playoff game, he's probably playing."

Keefe refused to divulge the nature of the injury, citing that it won't matter as Matthews will be over the ailment quickly.

"Given the time of year and the fact it's pretty minor and I think he's going to move past it pretty quickly," he said. "So, we'll just leave it at that."

Matthews, 24, suffered the injury during Saturday's 5-4 overtime victory over the Ottawa Senators and is considered to be day-to-day.

With six games remaining in the regular season, Keefe will need to consider balancing rest vs. readiness as the team prepares for the post season.

Matthews is in the middle of a career season where he has tallied 58 goals and 102 points in 70 games.