NEW YORK – The Phillies wanted to believe they could maneuver Taijuan Walker through the Mets’ lineup a couple times on Thursday night at Citi Field.

Instead, he reminded everybody how far he has fallen since last season and how much of a problem the team’s No. 5 starter has been for months.

“It just didn’t work out,” Phillies manager Rob Thomson said. “My fault. I’ll wear it.”

Walker allowed eight runs in 3 1/3 innings in a 10-6 loss to the Mets, postponing the Phillies’ shot to clinch a third consecutive postseason berth until no earlier than Friday, and their first NL East title in 13 years until no earlier than Saturday.

Walker allowed four home runs to the Mets: back-to-back solo homers to Mark Vientos and Pete Alonso in the first inning to make it 2-0, a two-run homer to Brandon Nimmo in the third to make it 4-2 and a three-run homer to Francisco Alvarez in the fourth to make it 7-3.

Walker is 3-7 with a 6.91 ERA this season. It is the sixth-highest ERA in Phillies history (minimum 80 innings pitched) and is also the highest for a Philly pitcher since 1930.

“It’s been a terrible season for me,” Walker said.

Walker, who has a 7.18 ERA in 15 starts, has allowed 24 homers in 82 innings overall, good for an eye-popping 2.63 home runs per nine innings. It is the fifth-highest home-run rate in MLB history (minimum 80 innings). To put that rate into perspective, Jamie Moyer allowed an MLB-record 522 home runs in his career. He allowed only 1.2 homers per nine innings.

“It’s never happened to me before,” Walker said. “I feel like I’ve been pretty consistent my whole career. Just going through this for the first time. It sucks. We’ve got a good team. I want to be a part of it and help the team as much as possible, and I’m just not doing my job right now.”

Walker had pitched OK as a reliever this month, posting a 4.50 ERA in three appearances after being demoted to the bullpen three weeks ago. He got bumped from the rotation because he had a 9.17 ERA in four starts following his return from the injured list.

The Phillies tried three different pitchers in Walker’s place this month, but none earned another start. Rookie right-hander Tyler Phillips allowed six runs in two-thirds of an inning on Sept. 3 in Toronto. Fellow rookie righty Seth Johnson allowed nine runs in 2 1/3 innings on Sept. 8 in Miami. Left-hander Kolby Allard allowed four runs in three innings last Saturday against the Mets.

Phillips, Johnson and Allard posted a combined 28.50 ERA in those three starts.

So, the Phillies returned to Walker. It backfired.

“The results just aren’t coming for me right now,” Walker said.

The Phillies chipped away at the Mets’ lead following New York's runs in the first and third innings. Walker threw 50 pitches through three innings, the most he had thrown in an outing since Aug. 28.

"I felt great,” said Walker, whose velocity was up more than 1 mph on all six of his offerings Thursday. “I didn't feel tired at all. It's frustrating, too, because I really felt like today was the best I've ever felt all year. I thought the stuff ticked up a little bit. Everything was hard."

Considering Walker’s recent workload and his 2024 track record, it could have been a spot for somebody else.

But the Phillies also are in the middle of a stretch of 13 games in 13 days.

“I’m not going to burn the bullpen,” Thomson said.

Walker opened the fourth by hitting J.D. Martinez with a pitch and walking Tyrone Taylor.

“It happened pretty quick,” Thomson said.

Walker threw a 2-0 fastball over the middle to Alvarez, who crushed the pitch to left field.

“Poorly executed pitch and he hit it out,” Thomson said.

Walker faced two more batters, with his night ending after that.

Phillies No. 5 starters have a 14.14 ERA in their past eight starts. The Phils are 2-6 in those games. Walker’s turn in the rotation comes up only one more time: Tuesday against the Cubs at Citizens Bank Park. Thomson did not say who will start, but he said his multi-inning relievers will pitch the bulk of the game.

That includes Allard and Tyler Gilbert.

When does Walker pitch again? Does this bump him from postseason roster consideration? These questions will be answered in the coming days and weeks.

Walker only promised to keep working.

“It hasn’t been a good year for me,” he said. “That’s what it comes down to.”