Orchard Park, N.Y. — The Buffalo Bills’ offense remains anemic and turnover-prone. And their defense is suddenly springing leaks again.

As if things can’t get much worse, the young and patchwork Bills follow up their 37-5 meltdown at Indianapolis on Sunday by preparing to host Tom Brady and the New England Patriots next week — and in a prime-time setting, no less.

Coach Sean McDermott acknowledged the challenge ahead by noting how the Patriots are far more accustomed to playing on a national stage such as Monday Night Football, as opposed to Buffalo — a team more familiar with early Sunday afternoon kickoffs.

“The better team you have, the more prime-time games you get,” McDermott said Monday. “So yeah, you can say give them the advantage because they’ve been there before.”

And that was after McDermott noted how relatively inexperienced the Bills are in saying: “I’ve got a young football team on my hands.”

It shows.

A year after ending a 17-season playoff drought, the Bills (2-5) are enduring the telltale signs of being in transition after going through yet another offseason roster overhaul as part of their intention to rebuild through youth.

One of those rookies won’t be in the lineup against the AFC East-leading Patriots (5-2), who are 31-4 against Buffalo in their past 35 meetings, and 7-0 overall in prime-time games.

McDermott announced rookie quarterback Josh Allen will miss his second game with a bruised elbow on his right arm.

That leaves veteran Derek Anderson preparing to make his second start some three weeks after being lured out of semiretirement.

The 13th-year player showed some rust by throwing three interceptions and losing a fumble against the Colts in his first start in nearly two years.

Despite his unfamiliarity with Buffalo’s playbook and personnel, Anderson did go 20 of 31 for 175 yards, which marked the most yards passing by a Bills quarterback in four weeks.

Buffalo’s offense, however, is at best a work in progress no matter who’s at quarterback, including Nathan Peterman, who lost the starting job midway through a 47-3 season-opening loss at Baltimore.

The Bills have scored just 81 points. It’s the third-lowest total in franchise history through seven games, and worst since Buffalo scored 75 in getting off to a 1-6 start in 1977.

The Bills have yet to top 20 first downs in a game. And the seven offensive touchdowns scored through seven games are the fewest over the same span since Buffalo managed six on offense to open the 2007 season.

The Bills have been so inept, only eight of 22 drives have crossed midfield over the past two games. The Patriots, by comparison, had six of 10 drives cross midfield alone in their 38-31 win at Chicago on Sunday.

“I think we’d all like to be out there posting 50 points (a game),” McDermott said. “That’s just not where we are right now. So we just have to understand who we are, where we are in this process of trying to get this thing going in the right direction.”

The game against the Colts was the latest indication of how the Bills stand little chance of being competitive if their defense unravels.

Though five offensive turnovers played a factor, Buffalo surrendered 220 yards rushing and four touchdowns passing — both season worsts. The Bills also forced no takeaways after generating 11 in their previous four outings.

The Colts scored on their final four possessions of the first half to build a 24-0 lead, marking the third time this season Buffalo has trailed by 22 or more points after two quarters.

It was an uncharacteristic outing for a defense that combined to allow just four touchdowns and had 15 sacks in its previous four games.

Coordinator Leslie Frazier described the issues against the run as being correctible.

“It’s disappointing,” Frazier said. “We’re trying to set the standard on defense, and we didn’t play up to our standard yesterday. It was not playoff-caliber, and we’ve got to play better.”

NOTES: RB LeSean McCoy’s status remains uncertain as he continues to be monitored for a concussion after being hurt on the second play from scrimmage. … Starting DE Trent Murphy is listed week to week after hurting his knee.

Anderson to start

Buffalo Bills coach Sean McDermott says rookie quarterback Josh Allen will miss his second game due to a sprained elbow and newcomer Derek Anderson will start against the New England Patriots next week.

McDermott continues to list Allen as week to week after he hurt his right throwing arm in a 20-13 loss to Houston on Oct. 14.

Anderson will start despite showing plenty signs of rust in throwing three interceptions and losing a fumble in a 37-5 loss at Indianapolis on Sunday. It was Anderson’s first start in nearly two years, and after being lured out of semiretirement to sign with Buffalo on Oct. 9.

The veteran quarterback finished 20 of 31 for 175 yards and was also sacked twice against the Colts.

The Bills are 2-5 and will host the AFC East-leading Patriots in prime time on Oct. 29.