Ladarius Green gives Steelers a vertical threat Heath Miller couldn't

San Diego Chargers coach Mike McCoy called the decision to sign Antonio Gates and not Ladarius Green "difficult." Christopher Hanewinckel/USA TODAY Sports

BOCA RATON, Fla. -- At this week's NFL owners meetings, the Pittsburgh Steelers commented on perhaps their biggest free-agent signing of the past two offseasons, former Chargers tight end Ladarius Green.

Here's what you need to know about Green, with help from Chargers coach Mike McCoy.

The Steelers have been tracking Green for four years: Once Heath Miller retired, coach Mike Tomlin revisited his draft file on Green, who was a fourth-round pick in 2012 out of Louisiana-Lafayette.

Then, the Steelers reviewed their scouting notes from game prep in Week 5 in San Diego. Green had started the previous three games while Antonio Gates was out, and he performed well with 174 yards and two touchdowns.

"We got a firsthand perspective," Tomlin said. "We had the opportunity to prepare for him even before Antonio Gates got back,. We believe he's a good player now. He has upside, room for improvement and can do exciting things for us -- to get a guy with both youth and experience at a position of need."

They've lacked a vertical threat at TE -- until now: Heath Miller did a little bit of everything for Pittsburgh's offense. He's a terrific run-blocker and has reliable hands. But bolting 40 yards downfield for a big gain was never his thing.

Enter Green.

"He'll bring us a dimension at tight end that we really haven't had," general manager Kevin Colbert told ESPN's NFL broadcasts this week. "Heath was a great receiver, a great blocker. He wasn't really a stretch the field guy. Ladarius gives you that added dimension of speed, he'll have to work on his blocking to get caught up to where we need him to be. But the speed and vertical threat at tight end is really something we haven't had."

The Chargers didn't want to let Green go: McCoy called the decision to sign Gates and not Green "difficult." The Chargers talked to Green's agent, Adisa Bakari, before free agency started. Green ultimately wanted to test the market.

"He's got a bright future in Pittsburgh," said McCoy, who has received calls from Steelers coaches about Green since the signing "Can't say enough good things about him. That was not an easy decision."

Versatility is a strong point in Green's game, said McCoy, whose offense moved Green along the formation.

"His knowledge of the game, and the big thing is his playmaking ability," McCoy said. "A very talented player in the passing game."

He's improving as a blocker: Tomlin called Green "much improved" as a blocker since his collegiate days. He's also jumped from 225 pounds to the mid-240s. Green said he maxes out at about 250.

"We're excited about the ways he can improve in that area," Tomlin said.