The hockey world is now imagining the Tampa Bay Lightning moving forward without Steven Stamkos. 

But the Pittsburgh Penguins have to consider what the Lightning will be like if Stamkos and defenseman Anton Stralman return to the lineup during the Eastern Conference Final.

Out since March 25 with a fractured fibula, Stralman returned to full practice Wednesday. Stamkos, on blood thinners because of a blood clot, has been skating with the Lightning for a while, although he has not been cleared for contact.

Neither player is expected to be ready when the best-of-seven series starts Friday (8 p.m. ET, NBCSN) in Pittsburgh. However, no one has ruled out seeing these players later in the series.

Among the most impressive aspects of Tampa Bay’s 8-2 playoff run is that they are doing it without two players who once seemed indispensable.

Stamkos scored 36 goals this season. That's the same number as Sidney Crosby. Stralman is a top-pairing defenseman who has a track record of performing well in the playoffs. 

The Penguins’ depth has been the talk of the playoffs. But how many teams could lose players of Stamkos' and Stralman's importance and still be in position to return to the Stanley Cup Final in back-to-back seasons? 

Even without those key players, the Lightning have remained as dangerous as they were in last year's march to the Stanley Cup Final.  

They are scoring three goals per game and giving up an average of 1.9 goals in these playoffs. Last season, they averaged 2.5 goals and gave up 2.29 goals per game in the playoffs.

Ben Bishop is a more advanced goalie than he was a year ago, and Nikita Kucherov is more polished scorer. Jonathan Drouin has blossomed into the offensive contributor the Lightning hoped he would be when they drafted him.

Center Tyler Johnson is playing with the same verve and production that he displayed last season at this time. That’s a major help because Johnson’s regular season was undermined by injury and decreased effectiveness.

The Lightning are showing they could continue to thrive next season if Stamkos, an unrestricted free agent this offseason, leaves.  Stamkos' future has been a subplot for the Lightning since the season started.

But Tampa Bay's Steve Yzerman has never been a reactionary general manager. He is a calculating administrator and a long-term thinker. He's unlikely to make any decision about Stamkos solely based on how well the team is playing without him.

It’s just another piece in the puzzle of whether the Lightning can re-sign Stamkos and still have enough money to pay the other talented players on the team. They also have six restricted free agents to sign and $52 million locked up in 15 players next season, according to generalfanager.com. Next year's salary cap is expected to be between $71 million and $74 million.

The Lightning have the team defensive game that will allow them  to slow down the Penguins. Though, It would be easier if shutdown defenseman Stralman returns.  But they can’t think like that.

It’s an unwritten rule in the NHL that players should never ponder the “what if?” of their situation.  It’s more productive for the Lightning to ponder how they will stop Carl Hagelin, Nick Bonino and Phil Kessel. And, oh yeah, Sidney Crosby and Evgeni Malkin, too.