Probably a combination of defense, fluke, and large park turning HRs into off-the-wall hits.

You’ve got a fly ball pitcher’s park and fly ball pitchers (more so when Johan is not on the DL)—outfield defense becomes paramount.

but it will be solved soon. Cuddyer is a serviceable right fielder he has poor range but an absolute cannon for an arm, Kubel is very slow with an average arm and ok instincts, Young has an decent arm but is an absolute butcher in left, Span has the speed and a good enough arm to play center but sometimes takes bad routes and is really hampered by the lack of defense on either side of him. The future is coming Benson and Revere are very good outfielders with speed, Benson is a great defender in all aspects and Revere is lightning fast but is hampered by a Johnny Damon esque arm though at least in his youth his blazing speed should make up for it, and Hicks is coming who should be a superb defender. They have already shown an they realize they need to gear the team somewhat to the park aka the off season “speed” need and I think this will continue in years to come. Water buffalos in the outfield dont play so well in a cavernous park and with Cuddyer and Kubel in contract years there should be at least 1 outfield spot filled by a speedster next year. Slowey and Baker really get hurt by the current outfield being fly ball pitchers, along with the rest of the staff, but help is coming park considerations take time and it is only the 2nd year of target field.