Because Pedro Martinez is 36 years old and last pitched a full slate in 2005, his latest injury comes as no surprise. It was expected and inevitable. This being so, there’s no reason why it should unnerve Mets fans at all. The news that Martinez will be out for 4–6 weeks with a left hamstring strain after just throwing 57 pitches may have been heartbreaking, but neither the injury nor an extended leave for the team’s no. 2 starter should affect the team’s chances at all.

The main reason for this is that the Mets are not especially reliant on Martinez. Baseball Prospectus, for instance, projected before the start of the season that the team would win 93 games, with Martinez pitching 125 innings. Both numbers seemed, and still seem, reasonable. With a deep lineup, a strong defense, and excellent frontline pitching, the Mets are a very good team that won’t be ruined by not getting innings they shouldn’t have been counting on. A full, healthy season from Martinez would of course have made the team even better; but then, so would a .400 batting average from Jose Reyes. One was no more to be counted on than the other.

Two ways of thinking about this should make the point clear. The first is that the Mets won 88 games and missed the playoffs by a game last year, when Martinez made only five starts, and are a better team now than they were a year ago. Johan Santana, rather than Tom Glavine, fronts the rotation; Jose Reyes and David Wright are a year older and a year closer to their absolute primes; John Maine and Oliver Perez have matured, and the team didn’t have a regular second baseman then, and does now. A minimal contribution from Martinez didn’t cripple them last year, and won’t this year.

The second is that because starters take the ball only every fifth game, even a long stint on the disabled list by a very good pitcher being replaced by a very bad one doesn’t, overall, affect a team as much as you might think. According to simple Marcel projections available at FanGraphs.com, Martinez looks good for a 3.83 ERA this year, which works out to 2.5 earned runs in the six innings he can be expected to pitch each start. By the same measure, Orlando Hernandez rates at 2.9 per six, Jorge Sosa at 2.97, and Claudio Vargas at 3.2. These are significant margins, but over 10 or even 15 starts they add up to a difference of a win or two.

As last year showed, a win or two can mean everything in a pennant race, but the Mets are good enough that they can sustain the loss. For them, Martinez’s greatest value is that he is, while aging and injury prone, still Pedro Martinez, quite capable of spinning a truly brilliant (and bullpen-resting) performance even when relying on nothing but guile and gamesmanship. When healthy, he has it in him to pitch at a Cy Young level for a month or two at a time, and help the team along on the kind of hot streak that puts distance between a first-place and a second-place team. Pitchers such as Sosa and Vargas may not kill the team’s chances, but they’re not going to make the difference.

Still, Martinez’s brilliance, given his age and health, has to be conserved, and if possible used when needed most. For the Mets, that will be September and October. And this is why Tuesday’s injury may, in the end, help them. While it’s too early to know with any certainty how long Martinez will be out, multiple months is a decent guess, given the nature of the injury. (The Yankees’ Phil Hughes missed three months after popping his hamstring on the mound last year.) This will definitely cost the Mets a few games in the standings, but it will spare Martinez’s surgically reconstructed rotator cuff the stress of relatively meaningless games against weak teams like Florida, games in which even weak replacements like Sosa can perform credibly. So far as that leaves the future Hall of Famer stronger and readier for the playoffs, it’s a good thing.

Certainly no team can count on a playoff spot it hasn’t won, and the Mets least of all, given the way last year turned out and the expectations in place for this year. If they’re near as good as most everyone thinks they are, though, they’re good enough to hold back a bit in games that count to give them better chances in games that count more. Martinez doesn’t need to rush or be rushed; he needs to do whatever is necessary to keep his tank full for the season’s seventh month. The Mets, their rotation, their bullpen, and even their anguished fans will survive.

tmarchman@nysun.com