Georges St-Pierre may be retired, but that didn't stop him from polishing his Muay Thai with Nico Carrillo in Thailand.
The MMA legend is scheduled to conduct a seminar on Saturday, local time, but decided to get his reps in before he teaches his classes.
GSP ultimately found the perfect coach to help him on his already lethal arsenal, and that man was Carrillo.
Taking to Instagram, St-Pierre showed his padwork with the Scottish knockout monster, who treated him like they shared a strong relationship as coach and student.
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St-Pierre posted:
"Lots of fun learning lots of new things. Big thanks! 🙏🇹🇭❤️"
St-Pierre is often regarded as one of the greatest MMA fighters of all time and was a former UFC welterweight and middleweight world champion.
Carrillo, meanwhile, is starting his athletic prime and looks to dominate the ONE Championship Muay Thai scene.
The Scotsman is an impressive 4-1 in the promotion, with all four of his wins coming via knockout.
Starting his promotional tenure at featherweight, Carrillo knocked out Furkan Karabag in his ONE Championship debut before moving down to bantamweight and wreaking havoc in an entirely new division.
Nico Carrillo went on a warpath in the 145-pound and scored three straight knockouts at the expense of Muangthai PK Saenchai, former ONE bantamweight Muay Thai world champion Nong-O Hama, and Saemapetch Fairtex.
'King of the North' was then slated for a shot at Superlek Kiatmoo9's ONE bantamweight Muay Thai world title, but the Thai superstar pulled out of their ONE 170 fight due to injuries.
Nabil Anane eventually replaced Superlek, but that development halted Carrillo's momentum.
The 6-foot-4 stopped Carrillo in the first round to claim the ONE interim bantamweight Muay Thai world title.
Nico Carrillo elated to share his knowledge with Georges St-Pierre
Nico Carrillo may be busy training for his next match in ONE Championship, but he would never turn down the opportunity to train with one of history's greatest ever fighters.
Taking to Instagram, Carrillo said he was ecstatic to hold the pads for Georges St-Pierre and share some of his tricks with the MMA legend:
"An honour to share my Muay Thai knowledge with the greatest fighter ever 🐐 @georgesstpierre. Damn, I love @bangtaommuaythaimma"