Brandon Montour, who scored in overtime in the Panthers' 3-2 victory against the Maple Leafs on Saturday, cut the margin to 3-2 at 17:28 when he one-timed a clearing attempt off the boards.
Mason Marchment tied the score 3-3 at 59 seconds of the second period with a one-handed backhand flip of a bouncing puck after Giroux lobbed the puck into the offensive zone.
"We've got a lot of competitors in here," Marchment said. "I don't think we ever want to lose I don't think anyone's ever happy with losing, especially in this locker room. I think for us just put this one behind us and move on to the next."
NOTES: The Lightning, the two-time defending Stanley Cup champions, were flying from South Florida to Washington to visit the White House on Monday. … Stamkos became the first Tampa Bay player with four consecutive games with at least three points. … Kucherov extended his goal streak to six games, two shy of the Lightning record set by Brian Bradley in 1992-93. … Reinhart became the fourth Panthers players to reach 30 goals this season, joining Aleksander Barkov, Anthony Duclair and Jonathan Huberdeau. … Huberdeau had one assist to move to 114 points on the season, four behind Connor McDavid for the NHL lead.