PITTSBURGH -- Baltimore Ravens coach John Harbaugh was as flattered as he was surprised when he learned that the legendary Joe Greene had picked Sunday night for the Pittsburgh Steelers to retire his iconic No. 75.

"Wow! Did he really?" Harbaugh said earlier this week. "I will take that as an honor. Wow, that's something really special."

Yet another testament to the transcendence of Greene: He can forge common ground between even the Ravens and Steelers leading up to what should be another hard-hitting game between the fierce AFC North rivals.

The Steelers will officially take Greene's number out of circulation at Heinz Field. Greene will join defensive tackle Ernie Stautner (No. 70) as the only players to have their number retired by the Steelers.

To say the gravity of what will transpire Sunday night has been weighing on Greene would be an understatement.

"I've probably had several sleepless nights thinking about what a great honor this is, and can I be up to the task? I don't know. We'll just have to see," Greene said earlier this week. "I know that I'm going to get really emotional and I've always been an emotional guy. I just hope I can finish."

Greene's presence at Heinz Field should only add fuel to the Steelers players and fans. And they will already be fired up for Baltimore's annual visit to Pittsburgh.

"He's a great player and an even better person," Steelers outside linebacker James Harrison said of Greene.

Harbaugh agreed.

"Even when I was just a young coach coming into the NFL he always treated me with tremendous respect," the seventh-year Ravens coach said. "I was in awe of him, Mean Joe Greene. He was a tremendous player and just a tremendous coach too. He had an incredible career."

Indeed, Greene is widely considered the best player in Steelers history. That is saying something considering the Steelers could have their own wing at the Pro Football Hall of Fame.

Getting his number retired will rank a close second to his induction into the Hall of Fame as far as individual honors for Greene.

"I know getting up there and hearing the fans and seeing the fans and seeing familiar faces [that] it's going to be an emotional time for me," Greene said. "I hope I can do the Steelers and the fans and my family and myself well."

He already has.