The Pittsburgh Steelers bolstered their pass rush by signing veteran James Harrison, another step toward improving the defense.

Terms: Two years, $3.5 million

Grade: A: This was the easiest move of free agency for the Steelers, considering the circumstance. Harrison wanted to come back and wasn't going to cost too much at age 38, yet he gives the Steelers instant production after leading the team in sacks last season. Harrison has proven an effective rusher late in his career.

What it means: It means the Steelers can enter the draft with two reliable edge-rush starters in Harrison and Bud Dupree, freeing them up to select a young playmaker they can groom behind the scenes. Harrison's presence means continuity, from the coaches to the players. He's well-respected in the locker room and a go-to voice for coach Mike Tomlin.

What’s the risk: The Steelers can't play Harrison forever, no matter how obscene the weightlifting gets. They need a long-term solution at outside linebacker that former first-round pick Jarvis Jones didn't provide under his rookie contract. Overusing Harrison early in the year could have diminishing returns, though he's proven more durable than most expected into his late 30s. And the team still has Arthur Moats on the roster.