But the truth is that the duo — which shares a birthday today* — has a few things in common, even if their levels of success aren't even in the same universe.
Smoltz, who turns 42 today, and Irabu, who turns 40, were both pitchers who began their careers as starters before converting to roles in the bullpen. Both are also attempting comebacks this year.
Let's look first at Irabu, who left the major leagues in 2003, returned to play in Japan and then "retired" in 2008. This season, Irabu is planning to join the Long Beach Armada of the independent Golden Baseball League in California — Jose Lima(notes) is a teammate of his, believe it or not — and his season will open this month.
Irabu, famously called a "Fat Toad" by George Steinbrenner, was a starting pitcher for the first five years of his career before the Rangers moved him to the bullpen in 2002 at the age of 32. It wasn't a successful move. He had a 5.74 ERA in 47 innings of relief, mostly thanks to the 11 homers he surrendered. (His ERA was 2.03 in the 31 games he didn't give up a homer.) Irabu was able to save 16 games, but had four blown saves and a 3-8 record.
Why was Irabu so unsuccessful? He had an acceptable K-rate (7.1 K/9) and an acceptable K/BB (2.31), but his unforgivable was his propensity for serving up gopher balls, as he averaged 1.6 homers allowed per 9 innings, higher than Eric Milton's(notes) 1.5 or Kyle Farnsworth's(notes) 1.4. He had a blazing fastball, and if he could have limited the homers, he might have been able to make a go of it in the bullpen. Instead, he washed out of the league and went back to Japan with only 34 major league wins to his name.
Compare that to Smoltz, who has 210 wins and 154 saves and is still rehabbing after shoulder surgery that ended his year with the Braves in 2008.
Smoltz moved to the bullpen when he was 34, midway through the 2001 season, and obviously did much better than Irabu. As a reliever in '01, he pitched 34 innings, saved 10 games, blew one save, and had a 1.59 ERA. We all know why Smoltz succeeded: He was the classic power pitcher with better than average control, a devastating slider and a punishing fastball. He was so good that he even managed a trip back to the starting rotation in 2005, pitching 229 2/3 innings at the age of 38 after only pitching 285 1/3 in the previous four years, and pitching 232 innings in 2006. Perhaps that's what led to his shoulder problems, but whenever he's been on the mound, he's been successful.
Smoltz hasn't given up, signing a one-year contract with the Red Sox. Neither has Irabu, though his chances of ever wearing a big league uniform again are minuscule.
Happy birthday to both.