According to a major league source, the Red Sox remain interested in trading for Mariners first baseman/outfielder Mike Carp, and remain, in the source’s words, “hopeful” that a deal for the 26-year-old can be worked out. Though Carp struggled in 2012, hitting .213/.312/.341/.654 in 59 games for Seattle, in 173 big league games, Carp has hit .255/.327/.413/.740 with 18 homers in 608 plate appearances. The Sox do view him as a potential upgrade over the inventory of left-handed-hitting first basemen/outfielders (including Lyle Overbay, Mark Hamilton and Mitch Maier) who are currently in camp (though, somewhat surprisingly, Carp has enjoyed more early-career success against left-handers — .300/.341/.462/.802 — than right-handers — .241/.323/.398/.721). In parts of nine minor league seasons, Carp has a career line of .276/.366/.465/.832. Carp could fill a pair of important roles with the Sox, as a left-handed alternative to both Jonny Gomes in left field and Mike Napoli at first base. Given that Gomes has had pronounced career splits throughout his career, enjoying much more success against lefties than righties, and that there are questions about the degree to which Napoli’s hip condition will permit him to stay on the field (perhaps requiring that he receive regular days off even assuming he avoids the DL), the Sox have made little secret of the fact that they would like to find a left-handed hitter who can partner with both players to sustain productive lineups. The Mariners have something of a logjam among first base/DH/corner outfielders, resulting in Carp getting designated for assignment last week. Seattle has until Thursday to work out a trade for him, though as of Tuesday, M’s GM Jack Zduriencik suggested to the Seattle Times that a deal involving Carp is likely to be concluded on Wednesday.