The Chicago White Sox made their third significant trade of the season Saturday when they acquired left-handed starter Francisco Liriano from the Minnesota Twins for infielder Eduardo Escobar and left-handed pitcher Pedro Hernandez.

The move my White Sox G.M. Kenny Williams seeks to add quality starting pitching depth to a team full of young flame-throwing relievers but short on healthy starters. The irony is that Liriano once was a thrower.

Liriano burst onto the scene in 2006 as an overpowering 22-year-old. Initially a reliever, the Twins promoted Liriano to the rotation where he finished the season 12-3 with a flossy 2.16 ERA and 1.000 WHIP. Relying on a 95 mph fastball and a sweeping 88 mph slider, Liriano averaged 10.7 K/9. However, Liriano’s impressive rookie year was derailed when he underwent Tommy John surgery on November 6, 2006. He would miss the entire 2007 campaign.

Liriano’s 2008 return brought a 6-4 record with a 3.91 ERA. However, Liriano’s pitches dropped about 4 mph and his K/9 dropped to 7.9. His WHIP increased to 1.395. Liriano’s troubles ballooned in 2009 when he finished with a 5.80 ERA and 1.551 WHIP.

Liriano appeared to have recreated himself in 2010 when he bounced back with a 14-10 record. He lowered his ERA to 3.62 and his WHIP settled to 1.263. His HR/9 also dropped to a career low 0.4. However, the last two seasons have been unkind to Liriano.

He is 12-20 over the last two years and his ERA has exceed 5.00. Part of Liriano’s 2010 resurgence can be attribued to a near return to his original velocity. His fastball averaged 93.7 mph in 2010. His fastball this year averages 92.8 mph.

Liriano’s current 5.31 ERA is marred by a terrible start; his April ERA was 11.02. However, June went smoothly to the tune of a 2.87 ERA and batters only hit .227 against the lefty in July. Signs of improvement?

The White Sox hope so. His FIPx (expected Fielding Independent Pitching) is 3.94, below the league average. The White Sox hope that pitching in front of the second best fielding team in baseball will lower his 64.8% LOB, amongst other unsightly statistics.

Liriano possess a live arm, but not the same arm that dazzled in 2006. The Sox are full of fireballers. They need a reformed hurler to perform like a pitcher.

The Big Guy