FOXBORO -- There is no replacing Dion Lewis.

Through seven games last season he rushed for 234 yards and two touchdowns, and he caught 36 passes for 388 yards and two more scores. He caught 72 percent of the targets sent his way by Tom Brady. He forced a whopping 43 missed tackles on his 85 touches, and he picked up 3.3 yards after contact per play. Plus, he was a force in the red zone, where with 13 touches he churned out 85 yards -- an average of 6.54 yards per touch -- and four touchdowns.

There is no replacing Lewis, something the Patriots found out in 2015 when he tore his ACL in Week 9. But because Lewis will have to begin the season on the physically unable to perform list, they'll have to try.

The most obvious and best-suited running back to fill the "sub back" role for the Patriots will be James White. The third-year player out of Wisconsin has had a strong training camp and preseason, showing good lateral movement and an ability to make defenders miss in space. He's also been one of the team's most sure-handed receivers. In two exhibition games he's caught three passes for 73 yards to go along with his 12 rushing yards on three carries.

Last season, filling in for Lewis as the team's primary receiving back, White caught 40 passes for 410 yards and four touchdowns. In the final seven games of the regular season, with an increased role, he reeled in 32 of those passes.

While White is a capable receiver -- he earned the third-best receiving grade in the NFL last season from Pro Football Focus behind only Theo Riddick and Danny Woodhead -- he is not the dynamic option Lewis was in the running game. The 5-foot-10, 205-pounder averaged just 2.5 yards per carry last season, more than two yards fewer than what Lewis (4.8 yards per attempt) posted.

Understanding that there isn't a single option who can provide the Patriots with what Lewis did last season, here is the rest of the Patriots picture at running back at the moment...

LeGarrette Blount (6-feet, 250 pounds): Blount opened eyes with his performance against the Bears last week. Showing good vision, an ability to change direction quickly and impressive power, he seemed to put to rest any questions as to who is considered the front-runner for "big back" carries in New England. Because Blount is not a factor in the passing game (18 receptions in the last three seasons), his role is not likely to change much with Lewis out, but he could potentially receive more work in the red zone where Lewis was so successful.

Brandon Bolden (5-11, 220): Primarily a special teamer over the course of his time in New England, Bolden has also been used as a versatile substitute in the running game. Because he's often active on game days for his kick-game contributions, and because he's a good athlete who has shown an ability to both run hard and be a dependable receiver, he's filled in both as a "big back" and as a "sub back" in emergency situations. Bolden has had trouble catching the football in training camp, however, and he lost a fumble to the Bears.

Tyler Gaffney (6-0, 220): Gaffney appears to be Blount's biggest competition this summer. They have tied for the team lead in carries this preseason (20), and Gaffney has 95 yards rushing to Blount's 89. The third-year back out of Stanford's numbers are bloated by a 44-yard touchdown run he had against the Saints in the preseason opener, but it seems as though the team wants to give him a legitimate opportunity to show what he can do after missing the last two years injured. Gaffney seems to be a more trusted option in the passing game than Blount, as he has caught five passes for 18 yards in preseason action. If he's viewed as a dual-threat back, he could be a hybrid backup option that forces defenses to remain a little more honest.

Donald Brown (5-10, 205): The 29-year-old has had trouble staying on the field during training camp and has yet to participate in a preseason game. When healthy, Brown could potentially give the Patriots more as a between-the-tackles runner than White, and he could potentially give the Patriots more as a receiver than Blount. He had eight catches in nine games last season but caught 29 and 27 passes respectively in 2014 and 2013. Patriots coach Bill Belichick praised Brown for his speed and his professionalism recently.

DJ Foster (6-0, 195): The undrafted rookie out of Arizona State is an intriguing athlete who showed great quickness at this year's NFL Scouting Combine. Like Brown, however, he has had a difficult time staying healthy enough to participate in practice. If he can get on the field and perform in this week's preseason game with the Panthers, Foster -- who played receiver in his final collegiate season -- would be an interesting depth option.

Joey Iosefa (6-0, 245): Another true "big back" with a similar build to Blount, Iosefa earned a promotion to the active roster last season after spending time on the Patriots practice squad. With an offseason in the system under his belt, Iosefa knows his role. His role on the team may be dictated, though, by the availability of others at that spot.