The last pitcher in the majors to pull of that feat was Buddy Carlyle of the Braves against the Padres on July 6, 2007. In the fourth inning, Khalil Greene, Russell Branyan, and Jose Cruz all fell before the mighty power of Buddy!
Pedro Martinez was the last AL pitcher to strike out the side on nine pitches back on May 18, 2002 against Seattle. Ichiro Suzuki, Mark McLemore, and Ruben Sierra were the victims in the first inning.
Three pitchers have done the 3 Ks in 9 pitches twice and they were a trio of has beens named Lefty Grove, Sandy Koufax, and Nolan Ryan.