When A.J. Cole made his major league debut for the Nationals last Tuesday in Atlanta, he gave up nine runs, four of which were earned, on nine hits, with one walk and one strikeout in two innings. Cole faced 17 batters, throwing 55 pitches, 30 of which were strikes. The 23-year-old right-hander went 0-for-1 at the plate and got off the hook for the loss when Washington rallied for a 13-12 win.

That’s a lot of numbers, but the number for Cole that got the most attention was the one on his back: 69.

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“I don’t have Twitter or anything like that, but I know people say stuff on there about it,” Cole told Sporting News. “Twitter and Instagram.”

Twitter is many things, but a haven of mature commentary is not necessarily one of them. The number 69 carries with it a connotation.

“Everyone said, ‘Are you on the offensive line?’ ” Pirates shortstop Jordy Mercer remembers of his time wearing 69 in 2012. “Or something about it being a football number.”

There’s the football number connotation, yes, but 69 also is a number with a not-safe-for-work meaning, and Cole is right that the market for high school giggles is robust on social media.

“I think people looked at it, and you’d get a quick chuckle, but I don’t think I got worn out or anything for wearing it,” said Eric Fryer, who wore 69 when he was called up to the Pirates in 2011 and now wears 22 with Triple-A Rochester in the Twins organization. “I remember Chris Snyder, he was one of the catchers up there, he was on the DL rehabbing, and my locker was right next to him. He saw that I had 69, and he went, ‘That’s awesome! You gotta get a tattoo or something with that.’ … I wish I had some better stories for you than just Chris Snyder razzing me a little bit. Other than that, it was just wearing it and hoping for a lower number at some point.”

That is the case for most players with high numbers, but not all. The player listed by baseball-reference.com as the first of six to wear 69 wound up wearing a higher number.

Jordy Mercer (Getty Images)

And, it turns out, Alan Mills may never even have worn 69 in the regular season.

Mills, who wore 75 for most of his career with the Orioles and still wears it as the pitching coach at Double-A Bowie, is noted by baseball’s most indispensable website as having worn 69 on the 1990 Yankees. The Yankees’ media guide, in its section listing historic player numbers, says the same. On Mills’ 1991 Upper Deck card, he is in his pitching motion with 69 clearly showing on his back. There’s just one problem.

“My first year, my first big league camp was with the Yankees, and I had number 69,” Mills said. “I ended up making the team. I had a really good spring, and the roster was extended because of the lockout. When we got to New York (where the Yankees opened the season against the Rangers), they wouldn’t let me have that number.”

Jeff Goldklang, president of the minor league ownership consortium The Goldklang Group, shared with Sporting News a Yankees scorecard from the end of April 1990 that lists Mills’ number as 28. In video of a game from that July, which follows a spell in Triple-A and getting called back up to the majors, Mills still is wearing 28.

So, what gives? Is Mills the first player in major league history to wear 69, or isn’t he?

“I was up and down a lot,” Mills said. “I wore 28, 45, 50 — lot of different numbers. I was on that Yankee Clipper shuttle (the Yankees’ top farm team at the time was the Columbus Clippers). They may have given it to me one time I was up, but initially, they wouldn’t.”

Ray Fink, a Yankee Stadium bat boy in that era, told Sporting News that he remembered the team having a rule, dictated by ownership, that no player wear a number higher than 55. It appears that this rule did not apply with September callups, but Mills was not a September callup. It seems likely that the photo on Mills’ baseball card is from spring training, when he had not yet logged an inning above A-ball, and thus was given such a high number. The uniform numbers listed at baseball-reference.com come from sources including media guides. The Yankees said that much of the numerical information in their media guide comes from a book called Yankees By The Numbers, and that without electronic records of rosters, they cannot be sure that Mills being listed as 69 is completely accurate.

If Mills never wore 69, it means that Cole is only the fifth player to don it on his back in a major league game — probably. Peter Munro is listed by both baseball-reference.com and the Blue Jays’ media guide as having worn 69 for Toronto in 1999, but also 13 — a similar situation to Mills. Munro could not be reached for comment.

What we do know for sure is that the Pirates have been liberal about 69, because in addition to Fryer, the number has belonged to Bronson Arroyo and Mercer in Pittsburgh. Mercer, in fact, got it the year after Fryer.

“We had a chuckle or two,” Fryer said. “The next spring training, I thought maybe I’d get a lower number, and I moved down a whole number — I got 68 in spring training, and he was 69. It was like, OK, being young guys and low men on the totem pole, that’s what you get.”

Said Mercer: “It was different, I’m not gonna lie, for sure. It’s something that I didn’t really try to get, that number, but when you get that call up to the big leagues, you’re not worried about what number you have or whatever the situation is. You’re so excited to be there, you’re living the dream. All the hard work’s paid off and you get to experience something that you dreamed as a little kid. The number is the last of your worries.”

That was Cole’s feeling, too.

“In truth, I’m not really sure (about having a number preference),” said the Nationals hurler, who was not surprised to get 69 upon his callup, having worn it in spring training. “I’ve had a couple of different ones — 11, 18, 19, 37 — it’s not really a big deal to me.”

At a certain point, though, a major leaguer does get a choice of what number he wants.

“Going into 2013, the equipment guy called me and said, ‘Would you like to change your number?’ ” Mercer said. “It was like, ‘Yes, please.’ I got to change the number to something more to my taste, something I like, and I chose number 10.”

Mills chose 75 for the same reason that he wanted to stick with 69 as a member of the Yankees.

“I wanted to remind myself never to get comfortable,” Mills said. “I always wanted to try to have the same mindset I went into spring training with as a rookie, where it wasn’t guaranteed I was going to make the team. I kept that as a reminder to never get complacent or content throughout my career. … At the time, when I was a rookie and asked them to keep (69) they wouldn’t let me. I’m a rookie, so I’m not asking any questions. I’m just happy to have a uniform on. Whatever you want to give me — you can give me 0 or 106 — it didn’t matter, I was in the big leagues.”

Eric Fryer (Getty Images)

Mills was not allowed to keep his spring training number, and nobody else who has ever been issued 69 has wanted to keep it, except for one man — Arroyo.

“When I … got called up in 2000, they just gave it to me,” Arroyo said. “I didn’t say anything about it. It was a locker room at that time that was very segregated, very heavily dominated by the veterans. There wasn’t really room to ask for another pair of pants, much less a new uniform.

“They just gave me that number. … For me, it wasn’t a big deal, because for one, I was born at the end of February. I’m a Pisces. So, it looked like the two fish swimming around each other. The reactions I got for it were — well, the one I really remember — I was a young guy. I didn’t play that much, and I don’t remember a ton, but I was warming up one time in San Diego, and this guy was screaming at me. He went, ‘Arroyo! Yeah, 69! That fits you real good, ‘cause you suck!’ I remember that. I was warming up for the game, and it was like, ‘Wow, man, I never heard that. That’s pretty good.’ But I’m a superstitious guy, so once I got the number, I didn’t want to give it up.”

Arroyo, who is currently working his way back from Tommy John surgery, wore 69 for his entire tenure in Pittsburgh, making a total of 53 appearances with the number from 2000-02. That’s the most appearances by any player wearing 69, and Arroyo is the only player to wear it in multiple seasons. He would have extended that record, too, had he gotten his way.

“When I got claimed by the Red Sox, off waivers, they called me and asked me what number I wanted,” Arroyo said. “I said, ‘I’ve always been 69, so I’ll take that.’ When I showed up at my locker, they had 61 in there, so that’s how I got to 61, and I still have that number. They either didn’t have that in their repertoire, or they were like, ‘Hell no, we’re not doing that.’ I probably would’ve got chewed up in Baltimore or Yankee Stadium, so it was probably a blessing that they didn’t give me that number.”

It would seem that other than the Pirates, most teams would prefer to keep 69 out of circulation. The Nationals’ feelings on the subject will be tested when Cole returns for more than just a spot start — and he does figure to be back.

“I’ve played with him every year (since 2012),” said Nationals reliever Blake Treinen, who was traded with Cole from Oakland to Washington in a three-team deal in 2013 which sent Mike Morse to Seattle. “He’s got unbelievable stuff. He’s a big league player."

When Cole does come back, he does not plan to request a new number, nor does he plan to request to stick with 69. Whatever Washington gives him, he will gladly accept.

“A high number is a high number and a low number is a low number,” Cole said. “I’ve never really thought about what number I want in the big leagues or minor leagues or wherever. … The numbers don’t really mean anything to me.”