NEW YORK - Fernando Martinez the 19-year old rookie is now a permanent fixture in the lineup of manager Jerry Manuel with Carlos Beltran on the disabled list. However it has been a struggle at the plate for the native of Rio San Juan Dominican Republic in his two stints with the Mets since being called from Triple-A Buffalo.Mets starting pitcher Johan Santana, who has been making his own adjustments on the mound, was surly glad Martinez was in that center field spot Thursday afternoon at Citi Field, the same area where Beltran would be. Because with the Mets holding a slim 3-2 lead in the seventh inning against the St. Louis Cardinals, Martinez made a diving catch on a sinking line drive off the bat of Yadier Molina that ended the inning and a Cardinals threat to score more.And what did Santana, the two-time LatinoSports MVP Award winner and two-time AL Cy Young Winner say to Martinez about the catch when they retired to the dugout? “Nice catch kid, he said to me,” commented Martinez who has been struggling at the plate with a .167 average but playing a solid outfield at center, his natural position, and also in left field when called to do so.Santana (9-5) would get the win, his second straight since his bad outing of giving up nine runs to the Yankees June 14th at Yankee Stadium. The Mets for the first time since early June won a series, winning 3-2, thus taking three-of-four from the CardinalsSantana gave up two runs of which one was earned in seven innings. And he kept Albert Pujols from hitting the home run ball, a plus for Santana who leads all Mets starters in giving up the long ball with 12.“My fastball was moving all over the place,” said Santana who once again was ahead of batters though he would be removed after throwing 110 pitches and the velocity  resembled the old Santana, at times clocked at 96.  For the first time in his last eight starts he did not allow a home run ball, and Nick Evans gave him the run support he needed with a two-run double in a three run fourth inning.Martinez continues to struggle at the plate but the youngster, who many say may be too anxious, is also realizing that this is the time to make things happen. If it isn’t at the plate, and many say the production will come in due time, Martinez may as well do it on the field.  That has to help Manuel put a smile on his face as the Mets wait for Beltran to recover from a bruised bone on his right knee.And plays like the one Martinez made in that seventh inning may help his cause as to not being optioned once again to Buffalo. Because soon the Mets expect to get healthy again in the outfield as Angel Pagan, on the disabled list with an injured groin is expected to rejoin the team next week when the Mets hit the road at Milwaukee.“If I don’t hit I need to catch,” said Martinez after the game when asked if this latest stay with the big team will last.  “I need to catch that ball to keep us in the game. I want to play and I want to hit and I am still adjusting,” he said.And Santana has seemed to have made his adjustments. He, along with other Mets starters kept Pujols, 4-for-13 in the series off the bases and from hitting the home run ball.  “He is arguably the best hitter in the game and when you do that it is a challenge,” commented Santana about keeping Pujols in check.Frankie Rodriguez recorded his 20th save pitching a scoreless ninth. The Mets now prepare to host the cross-town Yankees for three games in the second inter league subway series of the season that begins Friday evening at Citi Field.e-mail Rich Mancuso: