A pleasant surprise for the White Sox, although it is only for half a season. Humber is not striking out alot of guys, but he is not walking many and he is not giving up many HRs. That is what Maddux did. Humber stats are close to Maddux's career averages.
The table below shows how Humber this year compares to Maddux's career numbers. Of course, Maddux pitched until he was 42. But even if I only went up to age 37, Humber would still be close and Maddux had a 143 ERA+, just a bit better than what Humber has this year.