Sidney Crosby's resurgence and a four-game winning streak have the Pittsburgh Penguins back in the playoff mix, though the assignments are about to become considerably tougher.

Minus Evgeni Malkin, the Penguins embark on a tough two-game trip beginning with Friday night's showdown with a Tampa Bay Lightning team that's yet to lose at home in the new year.

Pittsburgh's highly skilled offense has come alive with 17 goals during the club's longest unbeaten stretch since a six-game run Oct. 24-Nov. 6. Crosby's return to dominance has ignited the surge, though Malkin - the Penguins' leader in goals (23) and points (49) - has played a key role by recording a hat trick against Vancouver on Jan. 23 and contributing two assists in a 6-5 win over Ottawa in Tuesday's return from the All-Star break.

Malkin won't be available for this game or Saturday's matchup at Atlantic Division-leading Florida, however, with the All-Star center missing the trip to rest a lower-body injury.

"He's going to rehab it over the weekend. We're going to evaluate him when we get back and go from there," coach Mike Sullivan told the Penguins' official website.

Malkin's absence further reduces the options at an already thin center position. Nick Bonino hasn't played since Jan. 12 due to a hand injury and Eric Fehr will miss approximately a month with a lower-body injury sustained Tuesday.

With Malkin out, Pittsburgh (25-17-7) will rely even more heavily on its top line of Crosby, Chris Kunitz and Patric Hornqvist as it attempts to halt a three-game road skid that includes a 5-4 overtime defeat to Tampa Bay on Jan. 15. Hornqvist had a goal and two assists in that game while Kunitz did the same against Ottawa after missing the previous two with a lower-body injury.

Crosby was the biggest difference-maker Tuesday, however, scoring three straight goals to rally the Penguins from a 4-3 deficit and record his first natural hat trick since December 2010. The two-time Hart Trophy winner has eight goals and six assists over an eight-game point streak and a league-high 14 goals since Dec. 26.

''I think he's doing the same things; he's going to the right areas and the puck is going in,'' Kunitz said. ''The confidence thing obviously for everybody on the ice when he gets going, gets everybody going.''

Tampa Bay (28-18-14) can counter Pittsburgh's high-powered attack with a defense that's yielded 20 goals over a 9-1-0 stretch and 13 over seven consecutive wins at Amalie Arena. Ben Bishop has allowed three in his last three home outings after a 24-save effort in Wednesday's 3-1 win over Detroit, which moved the second-place Lightning two points ahead of the Red Wings in the Atlantic.

"This was a big game, one of the bigger ones of the year, if not the biggest," said Bishop, 5-1-0 with a 1.59 goals-against average over his last six starts. "We're going to enjoy this for a couple of seconds and get ready for Friday."

Nikita Kucherov had a goal and an assist to continue his offensive surge. The 22-year-old Russian has matched Crosby with 30 points (15 goals, 15 assists) in 24 games since Dec. 5.

The Lightning went 2 for 3 on the power play and are 5 of 18 over the last four games after a 2-of-21 showing through the previous eight.

Pittsburgh is 6 of 16 during the win streak and has converted 27.1 percent of its chances since Sullivan replaced Mike Johnston as coach Dec. 12. Tampa Bay has killed 20 of 21 short-handed situations over its past six, however.