One of best discoveries of Bill James, father of sabermetrics, was the concept of “old player skills”. It was, ironically, more of a scouting insight than a statistical one (though he found support for the concept in the numbers), and like many of Bill’s best insights, it is a concept that is completely understandable without any reference to numbers at all.
To explain “old player skills” think of former Brewer first baseman Prince Fielder. The hefty slugger could drive a baseball like few others, but his size and general lack of athleticism limited him to first base only. Big boppers like Prince can’t rely on defensive prowess, base-stealing, or arm strength for added value and need to bat at an elite level to remain valuable at all. Because these players have all of their eggs in one “value basket”, and because the bigger guys tend to have more knee problems over time, the prototypical Prince Fielder types tend to break down hard when they break down, often finding themselves out of baseball in a hurry. Fielder was actually forced to retire at age 32 because of neck issues, and while there are exceptions to this rule, like David Ortiz, there are 10 Travis Hafners for every age-defying Ortiz.
More athletic players with power tend to age into “old player skills” players as they lose their speed, and as a result tend to have longer careers. Ken Griffey Jr, one of the most athletic players in baseball history, had a 30 home run season at age 37 while batting .272/.372/.496. Old Man Jr. was never as valuable as he was when he was young, but even after his secondary skills eroded, his bat kept him around the league for 21 total seasons. Jr. declined from a great player into a fine, if average player.
A “five tool” football player isn’t really a thing like it is in baseball, but when I think of what a five tool football player would be, Charles Woodson springs immediately to mind. Woodson could cover like an elite corner, hit like a safety, rush the passer like a skilled edge rusher, pop running backs, and to top it all off, he was one of the finest return specialists the league has seen. Woodson played his first 8 seasons/106 games for the Oakland Raiders before Ted Thompson took a shot on the 30-year-old in free agency. In the 4 seasons prior to joining the Packers, Woodson never once played in all 16 games, averaging just 11 per season and playing in just 6 in his final season with the Raiders. This was a perfect storm for Thompson, who caught a rare 5-tool player with elite athletic skills at the absolute bottom of his value. Woodson would play 106 games for the Raiders (in his first stint) and pick off 17 passes. He would go on to play 100 games for the Packers and pick off 38 passes, winning a title in the process. Because Woodson could do so many things, any decline he might suffer in one area could be offset with other skills. You could easily argue that Woodson didn’t decline at all and in fact got better, but his varied skillset allowed Thompson to take the risk in the first place.
There may also not be a better example of a 5-tool defensive lineman than Julius Peppers. Like Woodson, Peppers was touted as an athletic superstar out of college, and like Woodson he was a high draft pick, going 2nd overall to the Panthers. Peppers proved to be elite as a pass rusher, one of the single most useful skills in football, while also excelling as a run-stopper and, when rarely called upon to do so, a pass defender. In fact, for players classified as defensive ends since the merger, Peppers is tied for 5th all time with 11 interceptions, and if he can get one more before he hangs up the spikes, he will be tied for 1st. The Packers acquired Peppers at a later stage than they did Woodson, and his decline path was already clear, but that path still left them with an incredible pass rusher who could still show flashes in other areas occasionally.
Peppers and Woodson were both good bets to show some decline while with the Packers; however, they were both exceedingly likely to decline into very good players, and Woodson, as it turns out, debatably got better. Thompson may not dip into free agency much, but it’s pretty clear that when he does make a big splash, he is looking for elite talent with a diverse skill set.
This brings me to free agent corner Darrelle Revis, who turns 32 this year. I have seen a few pundits attempting to sell Revis as another Charles Woodson, capable of having a resurgent second half to his career. Revis was a good player in his youth, and in many ways an an elite athlete, having run a sub 4.4 40-yard dash at his pro day. That said, as far as corners go, Revis has the equivalent of “old player skills,” and it is much more likely that he will find himself out of the NFL in short order. It may sound odd to describe a player who once possessed elite speed in that context, but the problem for Revis is that his best skill by far was in coverage, and his speed was a big part of his success. Revis is also a talented technical corner who knows all of the tricks of the trade, and it is possible that he may still be valuable to the right team in the right scheme, but it is likely that he has lost a step, and likely his days as an elite player are over.
Revis is not a particularly sure tackler, he has 2 sacks in his career, and he doesn’t really have the frame or ability for safety. Once Revis can no longer play corner, there is really nowhere for him to go, just like a declining first baseman. Revis was great in his own right, but he’s not likely to rebound from his already stark decline, and he’s not a prototypical Packer free agent by any stretch.