LONDON — Most likely, Halapoulivaati Vaitai is the Eagles' right tackle for at least a few more games, in the wake of the second-degree MCL sprain Lane Johnson suffered on the first series of his team's ugly-but-important 24-18 victory over the host Jacksonville Jaguars Sunday at Wembley Stadium.

Vaitai gave up at least two of the four sacks Carson Wentz suffered, "Big V" playing at left tackle in place of Jason Peters — who missed the second quarter while being checked for a concussion — then playing the second half at right tackle for Johnson.

Coaches believe Vaitai does best when he knows he is starting on one side or the other and is given the whole week to prepare. Sunday was pretty much the exact opposite of that. Whether Vaitai gets his feet underneath him any better after the bye week might help determine whether the 4-4 Eagles have a chance to be more than just another middling team this season.

"When they tell me to go to left tackle, I'm like, 'OK, cool.' Tell me to go back to right tackle, I'm, 'OK, cool.' People make it hard because they overthink a lot of things. But really, you just do the same thing, on the other side," Vaitai said, after giving a hearty endorsement to fish and chips to a British reporter who wanted to know what he liked about his international adventure.

"I've just got to not let anything get in my head," said Vaitai, who in the preseason seemed to lose all the confidence and poise he'd gained after stepping in for Peters last October. The 2017 Vaitai wasn't great, but he was good enough for the Eagles to win the Super Bowl, without giving up a sack. The 2018 Vaitai has not been the same player.

Vaitai's worst moment Sunday might have come with about 6 1/2 minutes remaining. The Eagles needed to run some clock and maybe at least get a field goal, after Jacksonville got within 24-18, with 7 minutes remaining.

They couldn't do it, even after a replay ruling erased what had been ruled a Josh Adams fumble. Yannick Ngakoue got around Vaitai and sacked Wentz, setting up a third-and-13 the Eagles couldn't pull off. Fortunately, after Jacksonville got the ball, the defense held on fourth down.

"I overdid it," Vaitai said, meaning he overreacted to a stunt and was out of position. "I knew there was a chip [block] coming in [to help]. It was a natural 'U' stunt where the d-tackles just rush straight up the field. … Zach [Ertz, the chip-blocker] did his deal and helped me.

"No. 91 [Ngakoue] is really smart. I tried to grab onto him, but he's just really slick, and got around and got home with it."

When the defense created another chance to run down the clock the offense did so, all the way to the final whistle, which set off a huge roar from the pro-Eagles crowd of 85,870 – a record for the NFL series at Wembley. You would have thought Harry Kane had just carried Tottenham Hotspur to a huge Premier League victory.

"We came 8 hours across the water and fought a well-fought game and got a W," Peters said. "We just fought it out. Everybody was going here and there, but we got a W … 4-4 is way better than 3-5. … Keep Carson clean, get the running game going a little bit, and the rest'll be history."

Peters said he went into the concussion protocol "out of nowhere."

"On the interception [which ended the Eagles' second possession], I hit two guys, and they fell back. When I got up, the doctor asked me, was I OK? I just told him I was a little foggy, so I went right into the protocol. That's the league policy."

Left guard Isaac Seumalo seemed to do a solid job at right tackle while Peters was out, and Vaitai was in Peters' spot. Stefen Wisniewski played left guard when Seumalo had to move and got a snap at center when Jason Kelce was "kicked in the crown jewels," Kelce said, possibly puzzling local reporters who were under the impression those were under heavy guard in the Tower of London. Wisniewski even played a little third tight end.

Asked about all the moving parts, Wentz said: "You might think it's a big deal, but I got to give credit to the O-line. Those guys coming in, ready to go, it shows we have good depth there."

Against a big, strong, aggressive Jacksonville defense, the O-line did not take the penalties that have so often made the offense play from behind the chains.

"That's a great defense that we just beat," Peters said.

He said Vaitai "just has to settle down" if he is now the starter while Johnson heals. "Once he settles down, he'll be OK."

Healthy, Johnson is an elite right tackle, the Eagles' most athletic lineman. But he hasn't been healthy this year, suffering from a high ankle sprain that has dramatically curtailed his effectiveness. It's possible that if Vaitai can hold down the fort a bit, Johnson's ankle also will benefit from the downtime forced by the knee injury.

Kelce also credited the Jags' defense. He noted that the offense is putting up yards but not enough points – at one point Sunday the Eagles had 10 first downs and three points, which is not the ratio you're looking for.

"At the end of the day, we need to put up more points to help [the defense] out," Kelce said. "Today we did that a little bit better. Hopefully, we can do it even better after the bye."