Alex Rodriguez Does Dinner with Jennifer Lopez, Skips Derek Jeter Night

Alex Rodriguez was in NYC doing dinner with Jennifer Lopez ... while most of his old Yankees teammates were at Yankee Stadium honoring Derek Jeter.

A-Rod and J Lo stepped out Sunday evening heading to Nobu. They were dressed to the nines, but make no mistake ... this is a bad look for Alex.

Yankee greats gathered at the Stadium where Jeter's number 2 was retired. Alex was invited, but his publicist had said he wouldn't be able to make it because he was going to be in Miami celebrating Mother's Day.

The photo shows he was really just ... oh, about 8 miles south of Derek. We've reached out A-Rod's rep, but no word back yet.

First time in history choosing J Lo backfires?

7:30 AM PT -- A-Rod was indeed in Miami on Sunday. His rep says he spent the morning with family, including Mom. We're told he arrived in NYC after 6 PM -- he has to work there Monday -- and went straight to Jennifer's for the dinner.

For what it's worth ... the Jeter event went down around 7 PM.