He hasn't even given up the most homers of relief pitchers on this team. For the record, if we look at just the modern era of bullpens, since a bunch of relief pitchers were throwing 150+ innings back in the day, something called Gabe White gave up 18 in 2001 for the Rockies. Grimm has 11 and Rondon 10 this year. Jose Torres has given up 13 for the Padres this year.