Travis d’Arnaud did about all the Mets could have wanted this spring, but barring an injury to veteran John Buck wasn’t going to make the Opening Day roster. D’Arnaud’s fate became official yesterday, when the rookie catcher was among the players sent to minor league camp. The 24-year-old d’Arnaud, who hit .343 in 35 at-bats this spring, will begin the season at Triple-A Las Vegas. “[D’Arnaud] played very well, met all of our expectations, which for the organization and Mets fans were fairly high,” general manager Sandy Alderson said. “He did a very nice job, and I expect, hopefully, he’ll have a long career in New York.” Though d’Arnaud’s arbitration clock would begin this season if he’s called up to the major leagues before June, Alderson indicated he wouldn’t hesitate to make such a move if needed. “If John Buck gets hurt tomorrow, Travis d’Arnaud is the front-line catcher,” Alderson said. Aaron Laffey, Brian Bixler, Andrew Brown, Brandon Hicks and Jamie Hoffmann were the other Mets players sent to the minors yesterday. The lefty Laffey began spring training barely on the Mets’ rotation depth chart, but is now next in line for a starting job. Such is life for the Mets, who already have Jeremy Hefner ready to take Johan Santana’s rotation spot. Two other potential starters when camp began, Jenrry Mejia and Collin McHugh, aren’t in the immediate picture.