People come into our lives all of the time. Sometimes they’re important and life-changing forces; sometimes they’re just a momentary influence on us. We hope they’ll be permanent, but often their presence is fleeting. No matter what, however, they leave an impact on us, an impression of the time that we got to share with them; that’s what is truly important.

With Dion Lewis, though, I feel like we barely even got to know him before he left us.

No, Lewis isn’t gone forever, but he tore his ACL in the New England Patriots’ game on Sunday and will be out for the rest of the season. This revelation of a running back -- who not only replaced Shane Vereen but also forced head coach Bill Belichick to consider the option of a one-player backfield -- leaves us with a hole in our hearts and a gap in our fantasy lineups. How should we, as fantasy owners, approach this situation for the rest of 2015?

Who will be the next great Patriots’ running back?

Gone in 60 Seconds

For now, the Dion Lewis chapter of the 2015 Patriots’ story is finished. Who will arrive to take up his mantle, then?

If you look at the box score of yesterday’s game, you’ll see that LeGarrette Blount was given the first crack at the ball after Lewis went down, and he accrued 12 of the 17 running back opportunities (attempts plus targets) from that point on. The other member of the backfield to join in was Brandon Bolden, but he saw his first opportunity on a pass attempt with 12:17 remaining in the fourth quarter and accumulated just five opportunities over that time. Both of them have good potential to be highly-used going forward, with the likelihood that Blount retains early-down and goal line work and Bolden subs in on passing downs.

That said, there is one other player in the mix, who could scramble the certainty of the Patriots’ role-centered backfield split. James White -- a second-year fourth-round pick out of Wisconsin -- was inactive on Sunday but figures to enter the mix for passing-down duties. He was considered in the running for this role in preseason and training camp before Lewis burst onto the scene and may have a shot here. We also know Travaris Cadet was on the roster for a while, and he or another free agent could be signed once Lewis is put on injured reserve.

Who takes the jobs then?

The Next Man

In the one game that Lewis missed this year due to injury -- Week 7 against the New York Jets -- the Patriots decided to abandon the run altogether against New York’s impenetrable front seven. Lewis and Bolden were both inactive, and the team’s backs rushed five times for just a single net yard. They did pass to a running back five times, all to White, who converted three into catches.

It’s clear that they don’t expect or trust Blount to be a complete back based on their usage of him. But how have he and the other remaining New England options produced this year?

We can explore this question through the use of numberFire’s signature metric, Net Expected Points (NEP). NEP helps us take the numbers we get from the box score and assign them contextual value so they relate even closer to the game on the field. By adding down-and-distance value, we can see just how much each play and each team as a whole influence the outcome of games. For more info on NEP, check out our glossary.

The table below shows Lewis, Blount, White, and Bolden’s production in terms of Rushing NEP and Reception NEP through Week 8. Can we see any trends emerge so far, and who’s been the most effective?

It’s very clear that Lewis was not only the clear leader of this backfield in terms of volume but also value on raw and per-play bases. Blount follows in both regards, at least in terms of his Rushing NEP production, where he is the only other back who has given the Patriots’ positive contributions on the ground this year. In fact, in terms of Rushing Success Rate -- the percentage of rushing plays that generate positive NEP -- Blount is the 20th-best running back among backs with at least 40 opportunities in 2015.

Between White and Bolden, however, neither distinguishes themselves from the other at all. The former has just 17 opportunities this year and the latter has just 9, so small sample sizes certainly affect this production.

Still, even when we consider 2014’s production, White had a -0.30 Rushing NEP per play (nearly identical to 2015) and a 0.07 Reception NEP per play. Bolden had a -0.04 Rushing NEP per play and a -0.13 Reception NEP per play in 2014, slightly better than his competition but only marginally when one considers that they had 49 combined opportunities in 2014.

A Force of Two

It seems fairly clear that LeGarrette Blount is the only player in the Patriots’ backfield with a carved-out, certain role. He is by far the best rusher on the team and will continue to handle the early-down work in this offense. With nearly six additional rushes per week available from Lewis’ role, too, this will help to buoy Blount’s fantasy value. Our algorithms project him as the 22nd-best running back in standard scoring for the rest of the season, with around 91 carries for 377 yards and 4 touchdowns imminent.

He’s never been a great receiver but could see an uptick in receptions too; we like him to find 22 catches for 227 yards and a score for the rest of the season.

As for the passing-down role, it will likely go back to how things were when Vereen was in town. Last year, for instance, he handled 121 opportunities over the course of 16 games -- around 8 per game -- and accrued 838 total yards -- 52 per game. Our algorithms project this role -- currently owned by Bolden -- to generate 29 carries for 85 yards and 36 receptions for 244 and 2 touchdowns.

We had a glimmering flash of hope at the beginning of this year that New England would be a predictable running back situation, and all of that hope evaporated on Sunday. Still, we’ll always be grateful for Lewis’ contributions in 2015.