LeSean McCoy might be relaxing on the shores of Brazil this week, but retirement is not yet on the horizon for the Buffalo Bills' star running back.

There is unfinished business in the NFL for the six-time Pro Bowler as he approaches his 30th birthday in July. McCoy explained last summer that winning a Super Bowl would "put a stamp on his legacy," and said he is striving to reach 12,000 career rushing yards -- a benchmark for most Hall of Fame running backs.

The best way for McCoy to reach his goals will be to prolong his career. That will require the Bills easing the workload of one of the league's highest-mileage runners, so do not expect McCoy to be upset if Buffalo added another piece to its backfield this offseason and split carries more evenly next season.

McCoy's share of the Bills' running game has increased over his three seasons in Buffalo at a possibly unsustainable pace.

In 2015, McCoy accounted for 40 percent of his team's rushes and 37 percent of rushing yards, both career lows. McCoy missed four games because of injury but also yielded to rookie Karlos Williams, whose 5.6 yards per carry were second-most among running backs with at least 50 carries that season.

In 2016, McCoy played in 15 games, taking 48 percent of the Bills' carries and gaining 48 percent of their rushing yards. He was efficient -- his 5.4 yards per carry were a career best -- but not overworked. Backup Mike Gillislee took 21 percent of rushes and averaged an NFL-best 5.71 yards per carry.

With Karlos Williams' career derailed by substance-abuse suspensions and weight issues, and Gillislee signed away by the New England Patriots as a restricted free agent, the Bills could not find a consistent No. 2 option behind McCoy in 2017.

First-year coach Sean McDermott rolled the dice on Mike Tolbert, a player he knew well from their days together in Carolina, as the primary ball carrier behind McCoy to start the season. Tolbert, who turned 32 in November, accounted for 19 percent of the Bills' rushes -- and averaged 3.6 yards per carry -- until injuring his hamstring in Week 10. His share of carries dropped to 7 percent from Week 11 through the playoffs.

Tolbert's loss was Travaris Cadet's gain. Signed midseason, Cadet was the Bills' No. 2 runner from Week 11 until he fractured his ankle in Week 16. He took 12 percent of the Bills' rushes and averaged 4.3 yards per carry over that span.

The Bills leaned more on McCoy this past season than in either of his two previous years in Buffalo. His 59-percent share of carries ranked sixth in the NFL, and only eight players accounted for more than McCoy's 56 percent of team rushing yards in 2017.

The workload might have been less than when McCoy was a featured piece of Chip Kelly's fast-paced offense in 2013 and 2014 in Philadelphia, but that was earlier in McCoy's career.

McCoy now has the fifth-most career rushes (2,185) of any active running back, behind Frank Gore (3,226), Adrian Peterson (2,574), Matt Forte (2,356) and Marshawn Lynch (2,351). McCoy is more than two years younger than the rest of that group, so he is accumulating mileage at a faster pace.

Something will have to give. Either McCoy's tread will continue to wear, likely knocking him out of the league sooner than his peers, or he will take a reduced role that could prolong his career.

The key for McCoy and the Bills this offseason will be finding the sweet spot. Overworking him risks injury and lower efficiency of yards per rush. Underworking him will call into question whether he is worth the two years and $18 million that remains on his contract.

It is not hard to imagine McCoy starting the final chapter of his career back with the Eagles, or elsewhere, in 2019 or 2020. But for 2018, the model that could best work for the Bills is the one employed by the New Orleans Saints.

Mark Ingram, who turned 28 in December, was technically the Saints' starting running back this past season. He accounted for 52 percent of New Orleans' rushes and 54 percent of rushing yards. However, he split time with rookie Alvin Kamara, who took 27 percent of carries and led the NFL with 6.07 yards per rush.

Kamara also took pressure off Ingram in the passing game, catching 21 percent of New Orleans' total receptions -- the fourth-highest percentage among NFL running backs.

McCoy played a similarly important role in Buffalo's passing game in 2017, catching a team-high 20 percent of the Bills' total receptions. That was fifth-most among NFL running backs and the most he has contributed in the passing game since the 2010 season.

If McCoy can stay healthier, fresher and more explosive by the Bills cutting back on how much he is used in the running and passing games next season, it could be a win for both player and team.

Less is more if McCoy wants to someday see his bronze bust in Canton, Ohio.