Six weeks after trading R.A. Dickey to the Blue Jays, the Mets have made their move to replace him. The club has signed free-agent starter Shaun Marcum to a one-year deal pending a physical, a source told MLB.com on Thursday, plugging up the vacancy in their rotation. The Mets did not confirm the deal. Marcum, 31, went 7-4 with a 3.70 ERA in 21 starts for the Brewers in 2012, striking out 109 batters and walking 41 in 124 innings. He missed more than two months of the season with elbow tightness, following a bout of shoulder discomfort that sidelined him during Spring Training.