The Cardinals' No. 2 prospect struck out eight over six strong innings on Friday evening, but Palm Beach fell to the St. Lucie Mets, 2-0.
Martinez (0-1) retired the first seven batters before yielding a run on two doubles -- the only hits he allowed -- to Joe Bonfe and Danny Muno in the third.
"He made a good pitch. The switch-hitter is much better from the left-hand side. It was a pitch down and he went to it and hit it in the gap," Cards manager Johnny Rodriguez said of the sequence to Muno, the Mets' No. 17 prospect. "He only really made one mistake on the fastball in the middle of the plate to Bonfe; that was the only pitch he threw that I didn't like."
The 20-year-old right-hander walked three batters and plunked another but escaped unscathed over his final three innings. He is working to repeat his mechanics, according to his skipper. Rodriguez said he tells Martinez to keep his "line straight," baseball jargon for simplifying his athletic delivery.
"He gave us a quality start," Rodriguez said. "We challenged him, too. He was 79 pitches and we said go out there and get a quick [sixth]. ... He was much better than his first outing."
Martinez gave up two runs on five hits over four innings in his season debut, a no-decision on Saturday. His manager said he improved the use of his fastball, which hit 99 mph on the radar gun once but sat in the mid-90s, while mixing in more changeups to left-handed batters Friday.
"He's learning to pitch, learning to use his stuff," said Rodriguez, who previously compared Martinez to countryman Pedro Martinez when coaching him a year ago at Class A Quad Cities. "When you throw 97 inside and come back with a spinner in a two-strike count, oh my. He has three pitches that are going to get Major Leaguers out in the future. The delivery is starting to repeat more, which is helping him control his fastball and develop his secondary pitches. ... He feels like he's starting to take steps in the right direction."
Carlos Martinez, who signed out of the Dominican Republic in 2010 still hoping to be a shortstop, finished the 2011 season at Palm Beach, where he went 3-3 with a 5.28 ERA in 10 starts. He struck out 48 batters over 46 innings there but also walked 30. He has only 32 pro starts under his belt.
The Cards were held down by Mets starter Chase Huchingson, who gave up three hits and fanned five over six innings.
Huchingson (2-0), a non-drafted free agent who signed with New York in July 2010, has started the season with 12 2/3 scoreless frames. The left-hander, who turns 23 on Saturday, had not pitched above Class A before this year.
"He's a craftsman on the mound," Rodriguez said of Huchingson. "He can come inside, he can expand the zone, he can get up to 88, 89 with his fastball, mix in his changeup, curveball. I was impressed with him."