If you plan on showing up at Eagles training camp this year, here's a small piece of advice: Don't wear a Cowboys jersey, or the team might ask you to leave. 

One fan learned that the hard way on Tuesday when he showed up to the Eagles' practice facility wearing a Dez Bryant jersey. 

The picture above comes from Ed Kracz, who covers the Eagles for Gatehouse Media. 

Although our Cowboys fan friend has a huge smile on his face in the picture, I'm guessing that smile didn't last long, because the Eagles eventually gave him an ultimatum: take the jersey off or go home. 

According to Kracz, the fan decided to stick around, which meant he had to take off his Dez jersey and his Cowboys hat. The fan also had a Cowboys tattoo, but fortunately for him, the Eagles didn't ask him to remove that.

If you're wondering why the Eagles are even monitoring jerseys at training camp, there's actually a reasonable explanation. 

Since 2013, the Eagles have been holding training camp at their practice facility, and due to the small space, fans are only allowed to attend if they're invited. For the most part, the Eagles will generally open their practice to a limited number of season ticket holders, charitable organizations, and corporate partners. 

Since everyone is there as an invited guest, the team doesn't want fans wearing a jersey of an opposing team, especially a team that everyone in Philly hates like the Cowboys. At least that was the explanation the team gave to CSN Philly. 

From 1996 to 2012, the Eagles held their training camp at Lehigh University, and during that period, fans were free to wear whatever jersey they wanted. According to Kracz, fans are also free to wear any jersey they want when the Eagles practice at Lincoln Financial Field, which will happen again on Aug. 6.