Colts Mascot Plunges Into U.S. Olympic Swimming Trials Pool At Lucas Oil Stadium

The home of the Indianapolis Colts has transformed into a massive swimming facility ahead of next week's Olympic team trials ... but Caeleb Dressel or Katie Ledecky weren't the first to break in the new tank -- it was none other than the NFL team's mascot, Blue!!

The beloved horse documented the christening on social media ... showing him prancing around with enthusiasm before jumping right into the newly built pool on Wednesday.

It's an exciting time in Indy -- the place that usually hosts Anthony Richardson and Co. has been going through quite the makeover for the past month ... with the stadium turning into the world's biggest swimming arena to host the trials on June 15-23.

The whole setup includes more than an acre of pool deck space ... which sits about 10 feet above the ground.

There will be two different sections of pools -- the competition area and a warmup section ... with the latter being blocked off by a big curtain.

Organizers set aside roughly 30,000 tickets for the festivities ... in hopes of filling up seats for a one-of-a-kind experience for spectators.

As for where the two million gallons of water came from ... constructors got it from the nearby White River.

Blue is clearly stoked about hosting the trials ... saying, "LET’S GOOOO."