Martinez was close friends with fellow Dominican Republic countryman Oscar Taveras, the promising rookie outfielder who died in a car crash last October after St. Louis was eliminated by the Giants in the NL Championship Series.
Martinez switched to jersey No. 18 to honor Taveras, and says he'll wear it the rest of his career.
''He was a friend, a brother,'' Martinez said through an interpreter Monday on the final day of the team's three-day Winter Warm-Up fan festival. ''I'm taking it bit by bit. This tragedy, of course, affected me.''
Cardinals uniforms will feature patches with Taveras' number and initials, and a decal will be placed inside the stadium, much like the ones memorializing the late Darryl Kile and Josh Hancock. Chairman Bill DeWitt Jr. said the team also is renovating a field in Taveras' hometown of Sosua, aiming to make it ''first-rate.''
A brief stint pitching in the Dominican Winter League provided Martinez with an outlet that helped him process the accident that also killed Taveras' girlfriend.
Martinez wax 3-0 with a 2.25 ERA and 26 strikeouts and two walks in 24 innings for Aguilas Cibaenas.
''It definitely helped me mentally to be able to focus on something else, to be able to concentrate on something else,'' Martinez said. ''I know what I need to do be in the fifth spot and I'm ready for the challenge.''
''I feel like yes, this is my spot,'' he said.
Martinez appeared in 57 games last season,including seven starts in midseason, going 2-4 with a 4.03 ERA. He's the top pitching prospect in the organization.
The Cardinals weren't anxious to block that path by chasing free agent Max Scherzer, who got a seven-year, $210 million deal with Washington on Monday.
The Cardinals have other pitching issues. They're monitoring the progress of 20-game winner Adam Wainwright from elbow surgery, Michael Wacha from an unusual shoulder injury and lefty Jaime Garcia from unproven thoracic outlet surgery.
''We're giving Carlos a great opportunity, but opportunity is just that,'' manager Mike Matheny said. ''He's going to have to go out and compete.''
''It makes the offseason for baseball fans enjoyable, to think of the what-ifs,'' Matheny said. ''Man, I could think of a bunch of guys that could come in here and compete for a job.''
''I don't see the urgency in running out and making a hasty decision that goes outside of what the business model and plan is,'' he said.
Lance Lynn, who has 48 wins in three years in the rotation, believes the biggest hurdle for Martinez will probably be adjusting to the work load. Counting a brief stint in the minors last year, he worked 99 2-3 innings.
''That's going to be a different thing for him. You have to know when to go after it and when to be able to back off and get through things,'' Lynn said. ''I threw 140 innings, 160 innings before I even got called up to the big leagues.''
Lynn preferred to ''wait and see'' how Martinez handles the adjustment when facing a lineup for the third time. He topped out at 88 pitches and never made it past six innings last season.
''He showed at times last year that he's got electric stuff,'' Lynn said. ''He's going to have to handle the pitching deep into games and staying under control and being able to get through those innings late in the game when they've seen him once or twice.''
Lynn has the security of a long-term contract after getting a three-year, $22 million extension a few days earlier. Last year he entered spring training competing for a spot in the rotation.
''You know it's going to take care of itself with the arbitration process, but just to get the whole three years situated so we don't ever have to go through it,'' Lynn said. ''Both of us feel like we got what we wanted and I'm excited about it.''