TMZ Sports has learned ... the 27-year-old hit up his go-to guy, Bobby Ortiz, in El Paso, Texas to get a new leg tat representing his high school football career, his college one (at UTEP) and his time in the NFL.

The ink was put on his left shin ... featuring his old Burges High mascot, El Paso mountains, and the 915 area code with a mariachi -- a hat tip to his time at UTEP.

The tat also includes the NFL logo and Jones' nickname, "Showtyme" ... which he also named the restaurant that he opened up last year in El Paso.

We're told Jones also got two other tattoos on his left and right thighs ... featuring the words "Relentless" and "Grit," which Ortiz tells us Jones wanted to always remember for motivational purposes.

Ortiz -- who's been tatting the Green Bay running back since he was 18 -- says he got the job done in two different sessions ... with each taking about two and a half hours to get done.

We're told the Pro Bowler -- who's UTEP's all-time leading rusher (4,114 yards) -- left some room on his shin so he can add another accolade down the road.

"He plans to add a Super Bowl trophy," Ortiz tells us, "when he wins it."