(CBS) Let the rebuilding begin.

The White Sox traded closer Sergio Santos, who they recently signed to an extension, to Toronto Tuesday for minor league pitcher Nestor Molina.

Molina, 22, went 12-3 with a 2.21 ERA and 148 strikeouts in 26 games (23 starts) with Single-A Dunedin and Double-AA New Haven. Eighteen of those starts game at the Single-A level.

A native of Venezuela, Molina originally signed with Toronto as a free agent in 2006. Like Santos, he is a former position player turned pitcher in the minor leagues.

The trade is somewhat surprising because Santos just signed a contract extension with the White Sox at the end of September. In his first season as the team’s closer, he went 4-5 with a 3.55 ERA, 30 saves and 92 strikeouts in 63 appearances. He ranked third in strikeouts among American League relievers.