With an efficient first-round series victory over the Detroit Red Wings and two wins in three tries against the New York Islanders, the Tampa Bay Lightning have survived the absence of their stabilizing force on the back end, Anton Stralman.

Thing is, Stralman's broken leg isn't healing as expected.

Lightning coach Jon Cooper told reporters that the club has been "baffled" by the defender's injury, and in addition to being unavailable in Game 4, Stralman is doubtful for Sunday's Game 5.

Stralman suffered a non-displaced fracture of his left fibula during a net-front battle with the Islanders' Anders Lee near the end of March.

Only Victor Hedman has logged more minutes than Stralman since the beginning of last season's playoffs.

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