TAMPA — Lightning forward Nikita Kucherov hunched over, on his knees, at the blue line. The nearly-full Amalie Arena was just about silent.Kucherov blocked a rocket of a shot from John Carlson wand left the game, limping heavily as he made his way down the tunnel, during Saturday night’s 5-2 loss to the Capitals.Immediately, you could tell something was wrong. Kucherov took one step after blocking the shot at his right ankle/shin area and then didn’t put any more weight on that leg.He tried to get back to the bench but ended up on the ice, hunched over himself. Officials stopped play and head athletic trainer Tom Mulligan came out to check on Kucherov.The NHL’s defending MVP left the ice under his own power but did so by gliding, still bent in half. He stayed on the bench for a couple of minutes before heading toward the dressing room.“You guys saw what happened,” Lightning coach Jon Cooper said. “I don’t have an update on him. Hopefully he’s going to be OK. Obviously, he’s a huge part of our team.”Kucherov is not be scoring at the historic clip he did last year when his128 points set the Tampa Bay franchise record and became the most ever scored by a Russian player in NHL history. Still, he’s been hugely effective for the Lightning. He leads the team with 33 points and his 10 goals are third to Brayden Point and Steven Stamkos.The play-making star set up two power-play goals in Thursday’s win against the Bruins. One was one of those plays that makes you wonder if he has eyes in the back of his head, a backward, no-look pass to Point. The other was a nice dish to Stamkos.Kucherov missed one game earlier this season after leaving the Nov. 19 loss to St. Louis earlier this year with a lower-body injury.The Lightning haven’t fixed all the mistakes. They opened with a big one against the Capitals. The play looked simple enough. Defenseman Jan Rutta held the puck behind the Lightning goal, to start the play. But his pass ended up in the goal instead.Wing Ondrej Palat cut across Rutta and had the puck go off his skate right. Capitals center Nicklas Backstrom picked up the loose puck for a point-blank shot on Andrei Vasilevskiy at 6:42 in the first period for the game’s first goal.It was exactly the kind of mistake the Lightning are looking to eliminate.Then later on, after the Lightning overcame the first mistake, the quick-goal issue arose again. The Capitals scored twice in 45 seconds of the third period to erase Tampa Bay’s 2-1 lead.First, Lars Eller scored on a one-timer. Then, Garnet Hathaway scored on a flukey play. His shot deflected off Vasilevskiy’s stick and wobbled past the goalie. Flukey or otherwise, the spurt gave the Capitals momentum.Even after Rutta ended his 30-game goal drought to bring the Lightning back within a goal at 11:06, T.J. Oshie responded to put the Caps up 4-2 just 1:03 later.Lightning captain Steven Stamkos was limited to one shot, which came late in third. ... Capitals center Alex Ovechkin, who entered with 48 goals and 91 points in 70 games against Tampa Bay had three shots and was pointless. ... Backstrom has 14 goals and 61 points in 51 games against Tampa Bay. ... Kucherov assisted on Point’s goal and has a 12-game point streak (nine assists, 18 points) against the Capitals. Information from the Associated Press was used in this report.