Steven Stamkos will miss the next 6-8 weeks, which means he’ll miss playoff action and the Lightning’s Stanley Cup chances have taken an automatic hit.

After suffering a lower body injury Tuesday night against the Toronto Maple Leafs, Tampa Bay Lightning center Steven Stamkos missed a second straight game Saturday against the Calgary Flames. But the news has gotten worse, with the team announcing their captain will undergo core muscle surgery on Monday and be out 6-8 weeks .

The Lightning are in second place in the Atlantic Division, 11 points clear of third place Toronto pending the result of the Maple Leafs’ game Saturday night. So they are virtually locked into a good playoff seed, as they entered Saturday in a tie for the second-best points percentage in the league.

The first round of the playoffs is scheduled to start the week of April 6, five weeks from now. So Stamkos is in line to miss at least that opening round of action, on the early side of his recovery and rehab timeline.

Tampa Bay won the President’s Trophy with the league’s highest point total last season, only to be upset by the Columbus Blue Jackets in a huge first round upset. After a slow start this season, the Lightning have been pretty dominate in looking like a team that could close the deal and raise Lord Stanley’s Cup in June. But now without Stamkos, their second-leading goal (29) and overall point scorer (66) this season, behind Nikita Kucherov in both categories, just getting over that first round hump will be a far greater challenge.

Stamkos will miss a chunk of time for the fourth time in recent seasons. He suffered a broken tibia in November of 2014, and missed 45 games that season. A blood clot issue cost him all but one game of the 2015-16 playoffs, and a torn meniscus in his right knee cost him 65 games in 2016-17.

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Tampa Bay ended a four-game losing streak with a 4-3 win over Calgary on Saturday. But their bigger picture outlook for the season has taken a significant hit, with Stamkos’ production and intangible leadership now unavailable from here into the playoffs.