There is, perhaps, no more relentless member of the Indianapolis Colts’ defense than John Simon. He is 6 feet, 1 inch and 250 pounds of pure hustle. He never stops, never flinches, never yields until the whistle has blown. Then he lines up for the next play and does it all again. “He’s going to go 100 miles an hour so you’ve got to block him and you’ve got to block him until the whistle blows or he’s going to be around the football,” Tennessee Titans coach Mike Mularkey said of the Colts’ outside linebacker. About the only time you do not see Simon’s high-motor pace of play is when he’s not on the field. And, after missing the past three games with a neck and shoulder injury, the Colts finally will welcome back the unremitting, edge-setting, quarterback-harassing Simon against an opponent who won’t be thrilled to see him. Simon’s game against the Titans in October was the quintessential Simon performance. He had a career-high 11 tackles (six solo), a sack, and his first career interception, which he inexplicably snatched out of the air and returned 26 yards for a touchdown. Now, he prepares to meet Tennessee once more this Sunday, hoping to have a similar impact.