Gio Gonzalez good last year, really good this year

When the Oakland A's traded Gio Gonzalez to the Washington Nationals last December for right-handers A.J. Cole and Brad Peacock, left-hander Tom Milone and catcher Derek Norris, baseball fans were scratching their heads. After all the left-hander was an All-Star in 2011 when he went 16-12 with a 3.12 ERA. He was just 26 years old and at the time of the trade would be under team control for four more years. Now, there is a chance that A's could face the 20-game winner in the World Series in part because of a trade that helped both sides. 

The question now is how far the Oakland youngsters can take them and can Gio continue as the ace of the staff that is now without Stephen Strasburg.

So, how did Gonzalez go from allowing 7.8 hits and 0.8 homers per 9 innings last season to leading the league with just 6.7 hits and 0.4 homers per 9 innings this season?

Last season, Gio threw 3406 pitches of which 2209 were fastballs and 842 were curves. This season, thus far Gonzalez has thrown 3092 pitches of which 2200 and 636 curves. What is interesting is that the increased selectivity of the use of the curveball has also increased its effectiveness.

Here is a look at the batting average against the Gonzalez fastball in 2011:

Batters hit .244 against the fastball and slugged 15 homers

Here is the 2012 Gonzalez fastball:

Batters have .223 with 9 homers against the Gio fastball this season

Here's the BAA on Gio's 2011 curveball:

Batters only hit .197 with just a pair of homersSo why reduce the use of the curve?

Take a look at the 2012 Gonzalez curveball:

Batters are only hitting .127 with just one homer allowed!So, while we do need to take into account that Gonzalez is facing other pitchers in the batter's box , clearly Gio has found a good mix of fastballs and curves this season (with obvious improved control) to make each pitch better and to make him a 20-game winner.