After going 4–4 with a 3.98 ERA and a respectable 1.35 WHIP in 14 starts at Harrisburg, he was promoted on June 21 to Triple-A Columbus, where he went 1–2 and accrued a 3.02 ERA in 7 starts, striking out 42 batters and walking 17. He was selected as a member of the World Team for the 2008 All-Star Futures Game in Yankee Stadium. Martis was called up to the major-league roster on September 2, with the intent of assigning him to the bullpen.
Martis's early success at Harrisburg led to his promotion to Columbus, where he demonstrated his skills by going 1–2 with a 3.02 ERA in 7 starts and striking out 42 batters while walking just 17. He was subsequently selected for the All-Star Futures Game and eventually called up to the major leagues on September 2, as part of the team's plans to utilize him as a relief pitcher.