A Rodriguez was signed by the Rockies out of the Dominican Republic in 2005, and spent his time in their organization in Rookie, Short season and low A ball, and was shipped to Tampa Bay in the Jason Hammel deal. He bounced between AA and AAA with the Rays, and was selected in the 2010 Rule-5 draft by the Astros to compete for the 5th starter job. (he was unprotected in 2009, but did not get selected). His minor league totals were 41-43, with a 4.56 ERA, 1.37 WHIP, 7.9 K/9, and 3.2 BB/9.
When you look at A Rodriguez's 'stuff', everything is described as average. He throws 88-94 mph fastball (91 mph average, 65% of his pitches), an average to slightly above average slider (78 mph, 25% of his pitches), with an occasional curve (76 mph), and change (83 mph). He's been described as a two pitch pitcher (fastball and slider), and in his first start in the majors, out of his 83 pitches thrown, 80 were either a fastball or slider. He's a fly-ball pitcher, which once again doesn't bode well at Minute Maid Park.
The Astros started him in the bullpen this year, then the light bulb went off, saying "Why are we trotting 36-year old Nelson Figueroa out there every 5th day, when we have a 23 year old who can possibly pitch for us the next 5-8 years?" So after 9 relief appearances, he has made 2 starts, his first was 5 shutout innings of the Reds; 5 days later he faced the Reds again and didn't fare as well: 5 innings, 5 runs, 8 hits, including 2 home runs. For the year, he's 0-1 (18 innings), 5.50 ERA, 1.33 WHIP, 6.5 K/9, and 3.0 BB/9.
He has a ceiling as a #3 starter IF he can develop a reliable curve or change, but that won't likely happen this year. But for a team like the Astros, this is a smart decision rather than Figgy throwing every 5th day.