James Harrison might not be performing at his peak anymore, but he's still garnered at least five sacks in each of the past three seasons. In three playoff games last year, at the age of 38, he racked up 2.5 sacks and 15 tackles. That's what makes it somewhat surprising to hear that the Steelers already demoted Harrison on the depth chart behind rookie T.J. Watt.

According to Steelers outside linebacker coach Joey Porter, Harrison will be a "relief pitcher" this year while Watt -- J.J. Watt's brother -- gets the majority of the reps.

"That's why he's here; he's going to fight it," Porter told the Pittsburgh Post-Gazette. "But his role is his role. He's a relief pitcher. Until we need you, the young guys are going to play. You're a good safety net to have; if somebody's not getting the job done, we happen to know we have a wily veteran that we can put into the game. But to be honest going in, we have two young first-rounders who shouldn't be tired. And when they do get tired, we'll make the adjustments we need to.

"I know the old guy wants to play but at the same time it's hard to get in there if those guys are doing the job. If they're doing their job and they're playing at a high level, the understanding is understood. You don't have to explain anything that you can see right there on tape."

Apparently, Porter didn't tell Harrison about the plan, because when Harrison was asked about it on Wednesday, he didn't sound like he was in the loop. Still, Harrison is willing to play his part.

"That's fine. I'm not worried about it, man," Harrison said, per the Post-Gazette. "Whatever they want me to do. I'm 39 years old and still playing football."

Harrison is the bigger name due to everything that he's accomplished in his career -- he leads the franchise in career sacks -- but it's Watt who will most likely be the better player in 2017. Age has the most to do with that. Watt is 22 and the future. Harrison is 39. and will probably retire within the next few seasons.

And Watt is already off to a great start. It's only the preseason, but in his debut, he notched two sacks. Heck, it was a dominant enough showing that Kendrick Lamar was talking about it.

Sack No. 1:

Sack No. 2:

Last year, Harrison appeared in 15 regular-season games and logged 586 snaps, which ranked 25th among all 3-4 outside linebackers, per Pro Football Focus. He's still an important player, though, and the Steelers would be wise to keep him fresh for the postseason, when they'll be forced to take down the Patriots

As our Ryan Wilson explained earlier this month, the Steelers' Super Bowl chances depend almost entirely on their defense and whether or not they can slow down the Patriots -- something they've failed to do in recent years. And how do you beat Brady? As DeMarcus Ware wrote recently, you hit him over and over again. 

With Watt and fellow first-round pick Bud Dupree starting on the edge, and Harrison coming off the bench as a dangerous "relief pitcher," the Steelers might just be able to do that.