Mike Gillislee just lucked into a new career. The restricted free agent running back received an offer from the New England Patriots, leaving the decision up to the Buffalo Bills to match the offer or allow their running back to go off to a divisional rival. The Bills decided to pass on the opportunity to retain LeSean McCoy's primary backup, which means he will be joining the running back stable in New England next season.

Refusal to match offer sheet

The deadline for the Bills to match any offer for their running back was Monday. The Patriots offered a two-year, $6.4 million contract to Gillislee.

Evidently, the offer was too rich for Buffalo's blood and they announced that they wouldn't match it as the deadline came and went. Buffalo decided to let the running back go, perhaps with the intent of drafting a new, cheaper backup for McCoy during the NFL Draft this week. The Bills will receive a fifth-round draft pick from the Patriots as compensation for the loss of their restricted free agent.

This is not the first time the Patriots have successfully poached a coveted player from the Bills this offseason. When free agency began, they were able to steal cornerback Stephon Gilmore. Gillislee may not have the same name recognition, but he will be just as essential to the team going forward.

Last season, he rushed for 577 yards on 101 carries, with his 5.7 yard per carry average serving as the best mark in the NFL.

Addition and subtraction

The Patriots have made it an unofficial team policy to have a wealth of running backs at their disposal at any given time. With LeGarrette Blount likely gone in free agency, Gillislee will be expected to undertake his role next season as one of the primary options in the backfield.

Dion Lewis and James White will also be in the backfield, looking to take some pressure off Tom Brady next season (not that he needs the help).

Meanwhile, the Bills will look for new answers in the backfield now that Gillislee is in New England. Jonathan Williams, who was drafted in the fifth round in 2016, will likely get the first crack at being McCoy's primary backup at running back.

He rushed 27 times for 94 yards last season. Fullback Mike Tolbert could also receive a bigger workload. Additionally, the Bills could now use their extra pick to select a running back at a position that is deep with NFL prospects for this week's NFL Draft. None will likely live up to Gillislee's 2016 season, though.