Brian Sabean, Giants executive VP, has been seen at Citi Field during the Mets-Nationals series this weekend, according to ESPN.com. The reason for the visit is unknown, but the Giants could be looking to upgrade at third base and the starting rotation, two positions at which the Mets have depth.

Current Giants third baseman Casey McGehee is struggling at the plate, hitting just .164 with one home run. Daniel Murphy, a free agent after this season, is currently playing third base for the Mets while David Wright rehabs his strained right hamstring. The Mets also have young Dilson Herrera waiting in the wings to take over Murphy's regular spot at second base.

San Francisco also has big problems in its starting rotation as Tim Lincecum and Ryan Vogelsong have struggled early this season. Matt Cain and Jake Peavy have landed on the disabled list with injuries, as well. The Mets have two top prospects at Triple-A Las Vegas ready to jump to the majors very soon in Noah Syndergaard and Steven Matz, which could make Dillon Gee and Jon Niese available. Syndergaard threw seven shutout innings last night, striking out ten, and he hasn't allowed a run in his last two outings. Matz has also been dominant in his last two outings for Vegas. He's allowed just one earned run on seven hits over fourteen innings, walking three and striking out seventeen.