Lightning trade Adam Erne to Steve Yzerman and the Red Wings

Adam Erne's tenure with the Lightning ended Wednesday.

Tampa Bay traded Erne, or more accurately his rights, for a fourth-round draft pick. Now Brayden Point is the Lightning's only remaining unsigned restricted free agent.

Detroit knows exactly what it's getting with Erne. New general manager Steve Yzerman, formerly with the Lightning, was the one who drafted him.

The 24-year-old Erne had something of a breakout last season, his first spent entirely in the NHL. He had 20 points and 40 penalty minutes (10 minors) in 65 games.

The 6-foot-1, 214-pound winger added physicality to the fourth line without drawing many penalties, earning his consistent spot in the lineup.

Erne was arbitration eligible this year but did not file. He was on a one-year, $800,000 contract this past year and is likely looking at a contract in the $1 million range.

So why did the Lightning trade Erne? Most of what Tampa Bay has done comes down to salary cap.

It's possible this move is to free up cap space for Point. It's unlikely general manager Julien BriseBois, however, would have signed other free agents who were good to have but not crucial if the negations for Point's contract was close.

The Lightning and Point's agent, Gerry Johannson, may have agreed on a range; if so, the length of the contract could be more in contention. BriseBois wouldn't jeopardize his team's biggest free agent unless it was absolutely necessary.

This trade might be along the lines of BriseBois's offseason goalie moves. He could be looking down the line to the salary cap being even tighter next year and foresee being unable to keep Erne at that point.

This will make the Lightning's training camp more interesting as another spot in the lineup will be up for grabs. Players like Alex Barre-Boulet, Carter Verhaeghe, Cory Conacher or Mitchell Stephens could have a path to the roster.