Sacrifice is at the heart of every champion. A necessary ingredient that can sometimes be hard to find in multi-million dollar professional athletes.

Milwaukee Bucks just found out their best player is putting his team first above all else.

Giannis Antetokounmpo agreed to a four-year, $100 million extension Monday to stay in Milwaukee. That's more money than Antetokounmpo ever dreamed off when he was growing up in Athens, but it's not the most he could have earned.

There's no doubt Giannis is worthy of a maximum contract. Not many players in the league possess his rare collection of skills. The Bucks know this better than anyone, and surely they would have caved into giving Antetokounmpo the max, but during negotiations something else came to the forefront.

Bucks general manager John Hammond, via NBA.com:

There was a max number out there, and that was discussed, discussed internally and externally. And the one thing we asked Giannis to do was take that into consideration as we move forward. Give us every opportunity. We want to become a championship-level team. There’s going to be guys and guys who have done that, players who have given back some. And it’s a little bit of the time, as we move forward, hopefully we’re going to have other guys with the organization willing to do that. Those small pieces can turn into a bigger chunk at some point.

Antetokounmpo sacrificed $6 million over the course of his extension. That may not seem like a lot but the Bucks undoubtedly got him down to that number so that they can be flexible with other moves.

Milwaukee is stacked with some of the best young talent in the NBA right now. Alongside Antetokounmpo there's former No. 2 overall pick Jabari Parker, this year's No. 10 overall pick Thon Maker, and some other nice pieces, namely Khris Middleton.

The Bucks are on the rise, and should be for years to come now with Antetokounmpo locked up.