What is troublesome about the Mets’ long-shot chance at contention is not their weakness. For it hardly takes a scout with two good eyes and an off-the-record nature to reveal that the Mets’ outfield is three men and a maybe. The problem is their strength — pitching. No doubt that is their asset. If you need confirmation, walk two or three steps in this camp and someone affiliated with the team will offer a version of “we should pitch pretty well this year.” But the true measure of strength is by comparison — there is a difference between being a good basketball player in a 45-and-over rec league and the NBA. So the Mets like their rotation. But will it be better than Washington’s with Stephen Strasburg, Jordan Zimmerman, Gio Gonzalez and plenty of back-end depth? Nope. Is it better than the Phillies’ with Cole Hamels, Cliff Lee and Roy Halladay (and if you say Halladay is a health concern, I would say not nearly as much as Johan Santana)? Are the Mets’ starters better than the Braves’? Even if you think Santana, Jon Niese and Matt Harvey are comparable to Tim Hudson, Kris Medlen and Mike Minor, well, tie goes to the group supported by superior relief. And Atlanta’s Craig Kimbrel-led bullpen might be the converse of the Mets’ outfield — the best unit in the majors. So within the NL East, the Mets’ rotation — which, again, is their strength — projects as better than just the sell-off Marlins’. If you want to include the whole NL then at least the Reds, Giants and Dodgers also look superior to the Mets. Thus, the 2013 Mets’ rotation, is about mid-pack in the league. And this is what the Mets do best. So how exactly do they win consistently when their offense — to a great degree because of that outfield — promises little and the pitching, by comparison, is fine, but not great? Obviously, the rotation would be a grade better if R.A. Dickey were still fronting it. He’s not. Maybe you could push it up a notch or two if you believed Santana would perform close to his prime, which he last came close to doing over a full season in 2010. “If Santana is a No. 1, then I think we are equal to any other team or better,” pitching coach Dan Warthen said.