You guys are great. Only hours after the below inquiry on Steve Simpson, the pitcher received from San Diego in the 1973 Jim McAndrew trade and who may have been called up to the big-league roster in 1974, I’d received all kinds of info about him.
To the pertinent question of whether he should be listed among 1974 Mets players, the answer is no. As you might see on the accompanying graphic — what passed for the “official” transaction record as kept by the Baseball Hall of Fame — Simpson’s 1974 recall by the Mets (highlighted in yellow) is designated “not to rep” meaning “not to report” or “NTR.” A million thanks to Jason for the record — he reports he’s also looking to get his hands on the official record for Greg Harts, the outfielder recalled along Simpson that day. Click the image for a larger look. Those are exactly the kinds of records I keep: Scribbled on paper!
Anyhow, as Jason explains, all players on the 40-man roster are recalled automatically when rosters expand but not all of them necessarily report to the team: That’s the technical distinction that led to Charlie’s initial question.
Others of you were quick to point out addtional facts. Although he’d been assigned a number — the same 43 worn by McAndrew in fact — he wasn’t long for the Mets, or anyone else. The New York Times reports Simpson retired on the first day of training camp in 1975. And the Sporting News says he died of a heart attack at age 41 in 1989.
For Niemann, 55 marks his sixth different Met uni number: He wore Nos. 
The Mets you have may have seen have inked gangly pitcher Freddy Garcia and outfielder/utilityman Rob Mackowiak to minor league deals and invited them both to spring training. The oft-injured and well-traveled Garcia has worn 34 everywhere he’s played: It will be interesting to see whether Mike Pelfrey has any attachment to it in the event Garcia makes the club. Macklowiak, who seems a threat to Marlon Anderson (lefty, multipurpose player, with a weak bat) will take what he’s given. He’s worn 59 in Pittsburgh, 10 with the White Sox and 12 with Washington.
