Less than a year after the Tampa Bay Buccaneers made Darrelle Revis one of the splashiest acquisitions of the 2013 NFL off-season, the star cornerback is on the move again — this time as a free agent to the New England Patriots.

The economics behind Tampa Bay’s desire to divest themselves of Revis were predictably complex, given the league’s byzantine salary-cap rules. But suffice it to say, Revis would have cost the Buccaneers’ front office a lot of money. On the field, though, he will bring a lot of value to New England. Last season, he ranked first among cornerbacks in Pro Football Focus’ play-by-play-based grading system (this data is behind a paywall), making it the second time he’s led the NFL in that metric over the past three years. (He also finished first in 2011.)

But more importantly, Revis’ 2013 contributions extended beyond the stat sheet. Paradoxically, a top-flight cornerback’s statistics — particularly his interceptions — tend to go down as he plays better.

Take the great Deion Sanders. According to Pro-Football-Reference’s Approximate Value (a measure of an NFL player’s overall value to his team), Sanders peaked during the 1996 season, when he was named first-team All-Pro while playing every game for the Dallas Cowboys. Yet that same season, he tied his career-low for interceptions in a season (two) — even a broken-down, 37-year-old Sanders had more picks with the Baltimore Ravens in 2004.

What was going on? Teams were afraid to throw in Sanders’ direction. He wasn’t accumulating interceptions because he rarely had the chance to do so. The same was true for Revis last season. Despite posting one of the lower interception totals of his career, he was effectively shutting off one half of the field, keeping receivers from getting open and/or scaring the opposing quarterback away from risking a throw in his vicinity.

Among qualified cornerbacks, only the Seattle Seahawks’ Richard Sherman discouraged opposing passes more than Revis. Teams threw in Sherman’s direction once every 17 snaps. Revis was targeted once every 15 snaps. Only two other CBs, the Atlanta Falcons’ Asante Samuel and the New Orleans Saints’ Keenan Lewis, even cracked the one-in-13 barrier last season. You can’t complete a pass if you don’t attempt it, so a lot of Revis’ value lies in this deterrent factor.

All of this isn’t to say that the Buccaneers were wrong to release Revis. They’re a rebuilding team with a new coach, Lovie Smith, and have little use for a veteran soaking up a massive amount of cap room and costing them an extra draft slot. But the Patriots are getting a cornerback who still ranks among the game’s elite.