MISSING IN ACTION: 1979 MARDIE CORNEJO

Here’s a fun card to make: a “missing” 1979 Topps card of former New York Mets pitcher Mardie Cornejo.
Take a look:

Cornejo is a bit of a mystery since he appeared in only one season of Major League ball (1978), and performed rather well, posting a 4-2 record with the Mets while posting a 2.45 earned run average over 25 appearances and 36.2 innings, all out of the bullpen.
So why no other action in his career? Anyone familiar with Cornejo and what happened?
Nevertheless it was awesome finding this photo of the guy so I could whip this card up for the blog.