PORT ST. LUCIE – The Mets’ starting rotation has been set, and there’s one mild surprise: Steve Trachsel will pitch the second game of the season. Staff ace Al Leiter is slated to start Opening Day April 1 at Shea and Trachsel Game 2 April 3. Shawn Estes will be the Mets’ No. 3 starter, while Pedro Astacio will pitch the road opener against Atlanta April 5. Jeff D’Amico rounds out the rotation as the club’s No. 5 starter.

Trachsel, who began last season 1-9 and was demoted to Triple A Norfolk at one point, rebounded to finish the season at 11-13 and was the only returning starter besides Leiter. Astacio was a free-agent pickup over the winter, while Estes and D’Amico were acquired in trades. Leiter, who pitched last season’s opener at Atlanta, finished the season 11-11 with a 3.31 ERA. A strained right hip flexor sidetracked the 36-year-old lefty from one exhibition start, but he returned last Sunday with a solid four-inning stint.

Last year, Trachsel was 9-3 with a 2.74 ERA after the All-Star break. The 31-year-old right-hander worked seven innings or more in 12 of those 14 outings. He’s also durable, making 225 consecutive starts since his lone stay on the disabled list in 1994.