Alex Rodriguez Coaches Kardashian Softball Game, 'I'm Terrible At It!'

Some good news, bad news for the Kardashian family -- they got Alex Rodriguez to coach their family softball game ... problem is, A-Rod tells us he SUCKS at softball!

J Lo's boyfriend showed up at the field Thursday and suited up for Team Kardashian -- aptly named the Calabasas Peaches -- featuring Kim, Kourtney, Khloe, Kris, Kendall and some other friends including Jonathan Cheban.

They were up against a team in red while cameras rolled for their show. We know Kendall and Kourtney got some practice swings in earlier this week ... we'll have to wait and see if it paid off.

Alex hit up Craig's in West Hollywood after the action where he admitted he's terrible at softball -- but says the game went well.