After Jeff D’Amico got torched by the Astros last Tuesday, the day before baseball’s non-waiver trade deadline, Mets GM Steve Phillips worked the phones to bolster the back of the Mets rotation.

Apparently he dialed the wrong number.

Phillips traded Jay Payton, reliever Mark Corey and minor leaguer Robert Stratton to Colorado for John Thomson and Mark Little. Thomson made his Mets debut last night and the Diamondbacks scorched him for seven runs on seven hits over six innings.

Only three of the seven runs were earned, but Thomson had no one to blame but himself for giving up Jay Bell’s 387-foot three-run homer in the fifth that broke open the second game of the doubleheader, a 9-2 Arizona win.

“I pitched against these guys [the Mets] earlier this season and did pretty well, and I wanted to come in, I guess, and subconsciously, I guess, show I could still pitch the same way as I did earlier in the season,” Thomson said. “I probably put more pressure on myself than I should have.”

Thomson put pressure on himself in more ways than one. He opened the third by committing the inexcusable blunder of walking the opposing pitcher, Miguel Batista. Then he bobbled a sacrifice bunt off the bat of the speedy Tony Womack. He was hoping to get Batista at second and didn’t get anyone.

Jeromy Burnitz dropped a very catchable line drive off the bat of Quinton McCracken, scoring Batista. Thomson intentionally walked Luis Gonzalez but then hung a pitch to Mark Grace, who came in with a .249 batting average. Grace ripped the ball into right and Thomson was down 4-0.

Thomson knew he might be in for a tough debut. He faced Arizona July 23, taking the loss in an 8-5 game. Five days before that, Thomson got the win in a 6-4 decision over the Diamondbacks.

Grace said the Diamondbacks knew what to expect.

“I heard Grace saying, ‘We didn’t even need a scouting report,’ Thomson said. ‘We’d seen him last week.’ “