TAMPA — The Lightning's 7-4 loss to the Senators on Tuesday was weird in many ways.Forward J.T. Miller racked up his first career hat trick.Goalie Andrei Vasilevskiy got pulled for just the second time this season.The Senators looked like they were playing pinball with the puck, a couple favorable bounces including a shot caroming off the skate of the Lightning's Chris Kunitz.Heck, even Wheel of Fortune host Pat Sajak made an appearance in the Amalie Arena press box (he has a place in Orlando).But the strangest sight? Many Lightning fans heading for the exits early in the third period. There was no drama in this one, no shootout heroics. Tampa Bay, which had won six overtime games in its last eight, got thumped in this one by a bad Ottawa (25-33-11) team."We've got to look within, we've got to dig deeper and commit to being a better, sound team," Kunitz said. "Can't have our goaltenders bail us out like early in the year, and we're paying for it now."It was the Lightning's first regulation loss in its last 11 games (9-1-1), and it was a costly one. The surging Bruins erased a three-goal, third-period deficit in Carolina, pulling within four points of first-place Tampa Bay. If Boston wins Thursday in Florida, Saturday's St. Patrick's Day showdown in Tampa will be for the Atlantic Division lead."Biggest game of the year," Miller said. "Should be an easy game to get up for. We have a point to prove after (Tuesday's) performance. I think our guys are going to have a chip on their shoulders and it should be a good game."The Lightning might want to fix its penalty kill by then.There were many reasons Tampa Bay lost this one. But the porous penalty kill continued to be a costly culprit. The Lightning allowed two power-play goals, marking the 10th time in 12 games it has given up a goal with the man advantage. That 31-for-45 success rate of 68 percent won't cut it come playoff time. The penalty kill has been a season-long struggle, entering Tuesday at 77.5 percent, 25th in the league.The penalty kill is just part of the defensive issues the Lightning has tried to fix in practices the past few weeks. The acquisition of defenseman Ryan McDonagh isn't going to magically fix it, though it helps. The anticipated return of top two-way forward Ondrej Palat (lower body injury) this month will be a boost. But this has to be a group effort."Defending is still an issue," defenseman Anton Stralman said. "We need to work on it. And puck management, high danger areas, all that stuff."Miller's first gave the Lightning a 1-0 lead four minutes in, but the Senators would score three unanswered to take the lead for good. The seven goals allowed matched a season-high for Tampa Bay.But don't blame this one on Vasilevskiy, who received a mercy-pull after the second period. A couple Ottawa goals came on screens, another two off wacky bounces. But Miller said Ottawa earned their bounces. Kunitz said the Lightning tried to outplay the Senators, not "out-compete them."That won't work against Boston.