It was a baseball-packed long weekend for Toronto Blue Jays fans as the team hosted the Oakland Athletics for a homestand at the Rogers Centre.

But Saturday's 7-5 loss to the A's left a sour taste in viewers' mouths, with a perplexing series of missed calls by the home plate umpire drawing harsh criticism from fans and analysts alike.

One could argue that bad calls robbed the Jays of a fair shot at winning on Saturday, and with the anger still simmering, one fan showed up to the series rubber match on Sunday carrying a sign critical of the ump's calls the day before.

It turns out that was somehow against the rules.

I fought really hard but they will not allow me in with my sign because it could be considered to be... get this... "critical of the umpire". "It might be seen to be saying the umpire did a bad job."@MLBUA @BlueJays#NextLevel pic.twitter.com/uMjehbXc5w

— CJ Hajer ⚾️⚕💉 (@CjHajer) April 17, 2022

Jays fan CJ Hajer arrived at Sunday's game at the Rogers Centre with an infographic sign that accurately depicts how calls from the previous outing impacted the outcome, a clever protest that was pretty much immediately shot down by venue security.

The sign is essentially just a printout of a report from UmpScorecards.com, which shows that home plate umpire Jeff Nelson botched a staggering 14 per cent of calls in Saturday's loss.

His strike zone seemed to arbitrarily change from batter to batter, frustrating pitchers and forcing hitters to wildly swing at garbage pitches in a futile effort to protect the moving target that was home plate. And this isn't even the first time Nelson has been accused of tilting the playing field against the Jays.

But apparently, signs critical of umpires are forbidden?

Hajer was told by Rogers Centre security that the sign would not be permitted because "It might be seen to be saying the umpire did a bad job." Well, yeah. That's kind of the point.

Indeed I was. Tried every version of "But this is FACT. Not opinion." etc. but no convincing him.

To the security guard's credit, he's the one who took the pic.😂 Also, if he didn't give in to my next-level pressure, I believe we can rest easy that RC security is pretty solid. https://t.co/F83mZMcvpt

— CJ Hajer ⚾️⚕💉 (@CjHajer) April 17, 2022

Hajer even asked to speak with a supervisor, but in the end, the sign was neatly rolled up and checked with Rogers Centre staff.

Sharing stats about a game is now “critical of the umpire” 🤔 pic.twitter.com/PcB1jMWsX0

— Funny Introvert (@NotTokenBlack) April 17, 2022

Hajer tells blogTO that though she understands and respects the rules for behaviour and signs at the Rogers Centre, "I just don't agree that my sign was in violation of those rules."

She contends that "The sign itself was purely factual," adding that "it wasn’t personal like saying 'Ump, you suck!'.

"During and after the game, various statistics-oriented people started posting empirical evidence of Nelson’s poor performance using pitch tracking data from Statcast. My sign reported statistical fact and mathematically calculated probability etc."

Hajer says that, in her opinion, "Jeff Nelson's home plate umpiring of Saturday's game was both subjectively and objectively bad. Even our TV and radio announcers – experienced experts – were audibly frustrated during the game at some of the outrageously poor calls."

Despite the outcome, Hajer says "I was actually very impressed with the Rogers Centre security. The guard was polite and understanding but was absolutely firm in the face of me mounting a not-insignificant appeal! It honestly made me feel good about the security in general at the dome."

"He even took the picture of me you see there before he checked my sign in. I picked it up after the game. I really need to make it clear that I was NOT prevented from attending the game whatsoever, as has been reported elsewhere. I simply was not allowed to bring my sign."

A Rogers Centre representative tells blogTO that while team supports fans showing team pride, homemade banners and signs cannot "interfere with the game, fellow fans' enjoyment of the game or carry disparaging, commercial, political religious, or obscene messages."

It is unclear how Hajer's sign violated any of these rules.

The Jays would go on to win their Sunday outing, taking the three-game series despite the questionable calls.