FOXBORO, Mass. — Bill Belichick and his New England Patriots players have been honest this week: They really don’t know a whole lot about their Week 5 opponent, the Indianapolis Colts.

The Colts, who visit Gillette Stadium this Thursday night, have not played the Patriots since October 2015, and just seven players from that game remain on their roster. Indianapolis also has a new head coach, with former Philadelphia Eagles offensive coordinator Frank Reich taking over for Chuck Pagano this past offseason.

“This is a team that we don’t know very well at all,” Belichick said Monday. “There are very few players on this team that we’ve played against with the Colts, and certainly with the new staff, even the ones that we have played against, it’s a new system. So, we’re starting from scratch with the Colts … on a short week. That’s a big challenge for us.”

Since Patriots fans likely are equally unfamiliar with this Colts team, here are six things you should know about Reich’s squad:

1. Andrew Luck is back
Indy’s franchise quarterback finally is healthy after missing all of last season with a shoulder injury, and Reich — himself a former NFL QB — hasn’t been shy about giving him a heavy workload.

Luck has attempted 186 passes through four games, tied for second-most in the NFL and just three shy of league leader Kirk Cousins (189). Luck is on pace for 744 pass attempts, which would shatter his previous career high of 627 set back in 2012 and break Matthew Stafford’s NFL record of 727 set that same season.

“I think probably any coach would be comfortable putting the ball in Luck’s hands,” Belichick said. “He’s a very good quarterback, and he has excellent skill players to work with.”

Luck is coming off easily his best performance of the season, completing 40 of 62 (!) passes for 464 yards and four touchdowns with no interceptions in a 37-34 overtime loss to the Houston Texans. (More on that in a moment.)

2. T.Y. Hilton likely is out
Luck likely will be without his No. 1 receiver this week, however, as Hilton is not expected to play against the Patriots after leaving Sunday’s game with a hamstring injury. Top tight end Jack Doyle also has missed the last two games with an injured hip.

Hilton, a four-time Pro Bowler who leads the Colts with 294 receiving yards this season, is the only household name in Indianapolis’ receiving corps. Ryan Grant and Chester Rodgers are the next men up on the depth chart.

In the backfield, the Colts are relying on two rookies: fifth-round pick Jordan Wilkins, who leads the team with 136 rushing yards on 38 carries, and fourth-rounder Nyheim Hines, who’s done little as a rusher (18 carries, 54 yards) but has caught a team-high 22 passes thus far. Second-year pro Marlon Mack (hamstring) hasn’t played since Week 2.

Hines, whom we mentioned as a potential Patriots target before the draft, is a particularly intriguing player.

“He’s very good with the ball in his hand,” Belichick said of the N.C. State product. “He’s a good receiver. He’s a good runner. He’s fast. He’s elusive in space, hard to tackle. He’s a guy you don’t want to give a lot of freedom and opportunity to.”

3. Darius Leonard is turning heads at linebacker
The second-round draft pick out of South Carolina State is an early Defensive Rookie of the Year candidate. He leads the NFL in tackles through four weeks with 54, ranks second in tackles for loss with seven and is tied for sixth in sacks with four. Leonard also is dealing with an injury, though, as he tweaked his ankle against the Texans and didn’t practice Monday or Tuesday.

4. The Colts are seriously banged up
As you’ve probably gathered by now, the Colts’ roster currently resembles a trauma ward. A whopping 10 players sat out Tuesday’s practice with injuries, including Hilton, Doyle, Leonard, starting strong safety Clayton Geathers and each of their top three cornerbacks (Nate Hairston, Kenny Moore and Quincy Wilson). That’s not good news for a team that’s preparing to play on four days rest.

Even kicker Adam Vinatieri was absent. He’s dealing with a groin injury.

5. Reich’s gamble didn’t pay off in Week 3
Not wanting to settle for a tie against Houston, the first-year head coach chose to go for it on fourth-and-4 from his own 43-yard line with 27 seconds remaining in overtime. Luck’s pass to Rodgers fell incomplete, the Texans completed one pass to move into field-goal range, and Ka’imi Fairbairn booted a 37-yarder to win the game and drop the Colts to 1-3 on the season.

Reich defended the move after the game and stood by his decision this week.

“What we said in the offseason was, ‘Guys, we’re going to be aggressive,’ ” Reich said Tuesday in a conference call with New England reporters. “‘There’s going to be fourth downs that we go for and we’re going to make some and we won’t. We’re probably not going to make every one. We’d like to make every one but we might not.’ The response has been very favorable.”

6. The rivalry is back on
… At least according to Colts general manager Chris Ballard, who made that memorable declaration after Patriots offensive coordinator Josh McDaniels reneged on his agreement to take over as head coach in Indy. That “rivalry,” though, has been remarkably one-sided since late in the Peyton Manning era.

The Patriots are 7-0 against the Colts since 2010, including two wins in the postseason. This will be Indianapolis’ first trip to Foxboro since the 2014 AFC Championship Game, which spawned Deflategate.

Thumbnail photo via Trevor Ruszkowski/USA TODAY Sports Images