The following are HR rates that pitchers will almost certainly be unable to sustain over the course of the rest of the season. Predicting the inevitable corrections before they actually happen could help influence the standings in your league.
Home runs allowed per nine innings pitched – On average, the typical pitcher allowed 1.12 HR/9 IP last season. Ideally, you want to look for hurlers with a number that is less than 1.00.
Jake Peavy .10 HR/9 IP - He's good, but more flyballs are going to leave the park, no matter how spacious Petco is. There isn't a fantasy pitcher I'd rather own other than Johan Santana, and Peavy is the odds-on favorite to win the Cy Young in the NL, but he's been getting lucky in limiting the long ball thus far. His career rate is 1.02 HR/9 IP, and while he is inducing more groundballs (1.26 G/F this season after a 0.92 mark last year), giving up one home run in 94 innings is a rate that simply will not last.
Also see: Brad Penny (.20 HR/9 IP), Tim Hudson (.29), Kelvim Escobar (.33), Chris Young (.33), Chad Gaudin (.35), Josh Beckett (.38)
Note: There's probably a little cause and effect regarding the fact both Peavy and Young appear on this list, as pitching in San Diego gives them a better chance of finishing 2007 with a low HR/9 IP. Also, this stat is the easiest figure to point to Beckett's huge turnaround season this year. He gave up 1.58 HR/9 IP last year, which was toward the very bottom of the league. He ranks seventh best in the category this year.
Carlos Zambrano 1.43 HR/9 IP – So that's why he has a 4.89 ERA. For his career, Zambrano has allowed a very solid .69 HR/9 IP. This year, it's more than doubled. The 14 gopher balls in 88.1 innings are as many as he gave up in 209.2 innings in 2004. His strikeout rate is way down (6.93/ 9 IP), but he's actually posting a better groundball to flyball rate this season (1.41 G/F) than last (1.21). He'll always battle control issues from time to time, but if Zambrano is truly healthy – and judging by his high pitch counts, one can only hope so – he's due for a big bounce back over the final 3.5 months of the season. Go get him.
Also see: Ervin Santana (1.87), Johan Santana (1.36), A.J. Burnett (1.30)
Note: Guys like Cole Hamels (1.46), Chuck James (1.43) and Boof Bonser (1.36) also have very high HR rates, but those numbers are in line with their career totals. They are flyball pitchers, and thus, far more homer-prone. Ervin Santana, Johan Santana and A.J. Burnett, meanwhile, have very good groundball rates and are due for a correction in HRs allowed from here on out.