Ranaudo, 25, is a product of Louisiana State University and was the Red Sox' first round pick in the 2010 draft (39th overall). He was drafted by the Texas Rangers in 2007 out of high school, but he did not sign. As a result, they have liked him for some time now. Ranaudo posted phenomenal numbers in Triple-A, working to a 2.61 ERA over 138 innings. He made his MLB debut this past August, pitching 39.1 innings over seven starts, going 4-3 with a 4.81 ERA (6.89 FIP) and a 1.398 WHIP.
The 25-year-old Ross is more established than his counterpart in Ranaudo, making his MLB debut back in 2012 and remaining with the big league club each of the past three seasons. With the Red Sox starting rotation quite full, he'll be expected to work out of the bullpen, where he holds a 3.27 ERA and a 2.38 strikeout-per-walk ratio. Ross posted an ugly 6.20 ERA overall last year, which was likely due to down strikeout numbers. In the two years prior, he was 10-2 with a 2.62 ERA in 127.1 innings.
This swap was of two young pitchers headed in different directions. Ross is more of an established big leaguer, and represents an upgrade in the Red Sox' bullpen, one that was in need of a lefty. He's headed to a team more built to win and will fit a need. While the Rangers are not expecting to win this season, Ranaudo is a good return, as he is likely still one or two seasons away from making a legitimate impact.
Overall, the swap is an even one, with the Red Sox taking the stability over the upside, while the Rangers take the upside over the stability, which fits to both team's needs.