Conventional wisdom suggests that Ruben Tejada is quickly maturing into the perfect Plan B at shortstop if the Mets lose Jose Reyes in free agency this offseason.

But Sandy Alderson, along with the rest of the team’s decision-makers, are concentrating on Plan A, which involves pairing Tejada with Reyes deep into the next decade….

Not only have the two developed a mentor-pupil type of relationship, they share the same agent, Peter Greenberg, and already have made plans to work out together this offseason at the Long Island facility Reyes uses.

– David Lennon, Newsday.

As recently as a few weeks ago, I figured that if the Mets re-signed Reyes they’d be best served sending Tejada back to Triple-A to play everyday and using some combination of Daniel Murphy and Justin Turner at second. The way I had it, Tejada’s superior defense at second wouldn’t be enough to make up for the difference in offense.

But Tejada keeps hitting — slap-hitting, but hitting nonetheless — enough so that it’s no longer clear that Turner is even a better offensive player. The two share an identical .314 wOBA, with Tejada’s driven by a higher on-base percentage and Turner’s by more power. Turner has much more production on his Minor League resume, but Tejada has been extremely young for every level — including the Majors now.

Murphy will outhit both of them and by a great enough margin that if the Mets believe he can capably and regularly play second without again getting injured, he should see most of the playing time there. But since Murph can also play first and third, and might yet get another go of it in left field, the Mets shouldn’t have too much trouble finding semi-regular opportunities for his left-handed bat.

Perhaps the best solution would be using a combination of Tejada and Murphy at the keystone, with Tejada starting behind the heaviest ground-ball guys — Jon Niese and R.A. Dickey — and Murphy also seeing time in left field against tough righties and at third or first whenever David Wright or Ike Davis need a day.

An infield of Davis, Tejada, Reyes and Wright should represent a strong defensive upgrade over most combinations the Mets have used in 2011, and Terry Collins should have little trouble finding chances for a viable, versatile left-handed hitter like Murphy (consider that the less viable [but more versatile] Willie Harris has 243 plate appearances in 2011).

That would leave Turner either coming off the bench as a better, less expensive fit for the Alex Cora role or spun for pitching in the offseason. Both could help the club.

Of course, all of that is predicated on the Mets re-signing Reyes — far from a safe bet right now.