San Diego Padres closer Heath Bell may be traded to either the Texas Rangers or the St. Louis Cardinals.

The Rangers may be the front-runners since they are in "substantive" discussions with the Padres for the right-handed reliever, according to sources with Fox Sports.

Meanwhile, the St. Louis Cardinals did acquire relievers Octavio Dotel and Marc Rzepczynski in a blockbuster deal involving center fielder Colby Rasmus.

However, according to the Post-Dispatch, the Cardinals still maintain interest in acquiring Bell.

Both the defending American League champion Texas Rangers and the St. Louis Cardinals are in tight divisional races and could certainly use the services of Bell in their bullpens. 

Bell is perhaps the best reliever on the trade market with his stellar 2.4 ERA and 29 saves, when the Padres have only won 45 games so far this season.

The Padres are shopping several players Ryan Ludwick or Aaron Harang on the trade market this year, since the team is in last place in the NL West, and is in a rebuilding mode. 

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