The New England Patriots have won three of their last four, but they will have had plenty of time this week to think about ways to solidify a suspect pass defense.

The Patriots have coughed up fourth-quarter leads in back-to-back games, and their trip to London to face the St. Louis Rams on Sunday has given them ample opportunity to think about their problems.

"There are a lot of things we need to work on," said New England coach Bill Belichick, whose depleted secondary has been picked apart in recent weeks.

With starting safeties Patrick Chung and Steve Gregory banged up, New England (4-3) has allowed an average of 338.0 passing yards and 14 touchdowns through the air in the last five contests.

During that stretch, the club has surrendered season-high yardage totals to Baltimore's Joe Flacco, Buffalo's Ryan Fitzpatrick, Seattle's Russell Wilson and New York's Mark Sanchez.

The Patriots remain alone atop the AFC East despite the problems with their pass defense, bouncing back from a one-point loss to Seattle in their previous game by beating the New York Jets 29-26 in overtime last week.

New England, though, blew a 10-point lead after three quarters, a week after giving up two passing touchdowns in the final 7:21 to the Seahawks.

The Patriots gave up 403 yards to the Jets and are allowing 376.0 per game. They have allowed 20 or more points in six straight contests.

"We'll go back, see what we can improve," cornerback Kyle Arrington said after Sunday's game. "It's all about getting better from here."

New England's offense could also get better, as the club has scored three fourth-quarter points in each of its last two games. The Patriots lead the NFL in total yardage, but they've recorded two offensive touchdowns in each of the last two weeks.

"We have to nail those things down," quarterback Tom Brady said. "A lot of those inconsistencies, you don't score points."

Brady will have to get by in London without one of his favorite targets. Tight end Aaron Hernandez, who played the past two weeks despite nursing a sprained ankle that kept him out of the previous three games, will sit Sunday to give himself an extra week of rest with the Patriots off in Week 9.

The Rams have certainly struggled to score points, ranking 26th in the NFL with 18.6 per game while averaging 315.1 yards of offense -- 28th in the league. St. Louis was better offensively in a 30-20 loss to Green Bay last week, reaching the 20-point mark for the first time since Week 2 as Sam Bradford completed more than 60 percent of his passes for the second consecutive game.

"Our mentality is that we can play with anyone on any Sunday," Bradford said. "And we're going to take that same mentality into the game next week."

St. Louis, though, will have to do a better job defending a star quarterback after the Packers' Aaron Rodgers went 30 for 37 for 342 yards and three touchdowns.

Before last week, the Rams hadn't given up 30 points in a game and had allowed 11.0 over their previous three contests.

The Rams, trying to avoid a third straight loss, have dropped all three games away from the Edward Jones Dome this season.

"They're excited," coach Jeff Fisher said. "They know the challenges associated with going across the pond, as they say, and they're looking forward to it."

The Rams are making their first trip to London while the Patriots are returning after defeating Tampa Bay 35-7 in 2009, also at Wembley Stadium.

"The time change, the travel -- that's certainly different than most normal games," Belichick said, "but it's not anything we haven't dealt with before. We've traveled to the West Coast. We're just going the other direction. Hopefully, we'll be able to deal with it."

The Patriots have won three straight over the Rams, including a 20-17 victory in Super Bowl XXXVI on Feb. 3, 2002.

New England has gained more than 350 yards in each of their last 16 games, tying the NFL record set by the Rams from 1999-2000.