Anthony Rizzo is just 23 years old, but he has already beaten cancer and been traded twice. Learning to handle middle and high pitches, then, has been a cakewalk by comparison. Rizzo's staggering improvement against stuff thrown above the belt is a major reason why the Cubs felt comfortable locking him up with a seven-year, $41 contract extension, with two club options that could make it a nine-year, $73 million pact.
During his rookie year with the Padres in 2011, Rizzo's long, uppercut swing produced little more than wind power against pitches thrown in the upper half of the strike zone. The 6-foot-3, 240 pound prospect hit like a banjo-strumming middle infielder, with an upper-half slugging percentage (.217) that was over 200 points below the major league average (.425).
Rizzo's slugging percentage vs. upper-half pitches, 2011
In 2012, Rizzo made significant progress in solving his above-the-belt troubles. He cut his miss rate against upper-half pitches from about 32% to 13%, and he raised his slugging percentage to right around the league average (.415).
Rizzo's slugging percentage vs. upper-half pitches, 2012
Rizzo is making plenty of contact again on upper-half pitches this season (14% miss rate), but it's much louder contact. He's slugging .661 versus above-the-belt pitches, and his six homers on upper-half pitches already triples his 2012 total (two).
Rizzo's slugging percentage vs. upper-half pitches, 2013
Just two years after ranking in the bottom 20 among MLB hitters in upper-half slugging percentage, Anthony Rizzo now keeps company with the likes of Bryce Harper, Carlos Santana and Chris Davis in the top 20:
Highest slugging percentage vs. upper-half pitches, 2013
Rizzo's progress against middle and high pitches suggests that his new deal could be a bargain for the Cubs, and so do his career comps. Rizzo has a 122 OPS+ in 532 plate appearances during his age 22-23 seasons, a mark similar to those posted by first basemen like Willie McCovey, Keith Hernandez and Kent Hrbek at the same age.
It remains to be seen if Rizzo can match Stretch's feats of strength or get on base like Hernandez (to say nothing of growing such an awesome 'stache), but he's off to a great start.