Strange as it may be, Belisle's actually pitching better this year than he did last year out of the 'pen. You might look at the ERAs (5.28 this year, 3.60 last year) and ask how this can be, but a closer look at the numbers bears out my statement...
2006: 1.55 WHIP, 4.28 BB/9, 1.37 K/BB rate, LOB - 81%, FIP (Fielding Independent Pitching) - 5.18
2007: 1.38 WHIP, 1.93 BB/9, 3.05 K/BB rate, LOB - 64%, FIP - 4.37
As you can see, he's walking far fewer batters and therefore has a greater percentage of strikeouts compared to walks. His WHIP is down as well. The main thing I see contributing to his (much) worse ERA this year is the fact that last year he was stranding an unsustainable 81% of runners on base. This year it's a more realistic 64%. Also, it seems as though the defense has been poor behind him (big shock there
), resulting in an ERA worse than how he's pitching.
All in all, Belisle is still just 27 and has a live arm. I think as he continues to grow as a pitcher, (and if the Reds ever get a decent defense) he could become a very serviceable #4 or #5 starter.