In a surprise move, the Giants are expected to announce Friday that catcher Bengie Molina has re-signed with the club for one year at $4.5 million.

It was previously thought that Molina and the Giants were going to part ways this offseason as the veteran catcher was seeking a multi-year deal.

Given Molina’s age and the fact that the Giants had their catcher-in-waiting in Buster Posey, the Giants were not prepared to offer Molina a multi-year deal.

In recent weeks, it appeared that the Mets were all set to sign Molina. But Molina was still seeking a multi-year deal and the Mets apparently were not ready to give him. Figuring that if he was only going to get a one-year deal, it might as well be with the Giants.

This signing instantly boosts the Giants’ other offseason moves. While it appeared the Giants would simply be treading water with the signings of Mark DeRosa and Aubrey Huff, the addition of Molina gives the lineup of 2010 a definite improvement over 2009.

Consider the potential lineup for 2010 compared to the lineup at the start of 2009.

Pos   2010 lineup           2009 lineup
C — Bengie Molina        Bengie Molina
1B–Aubrey Huff            Travis Ishikawa/Rich Aurilia
2B–Freddy Sanchez     Emmanuel Burriss/Eugenio Velez
SS-Edgar Renteria        Edgar Renteria
3B-Pablo Sandoval       Pablo Sandoval
LF-Mark DeRosa          Fred Lewis
CF-Aaron Rowand        Aaron Rowand
RF-Nate Schierholtz/    Randy Winn
     Eugenio Velez/
     Andres Torres