All the way from a blind pick, and an extra Teemo in professional games, to the championships we have today, the pick and ban phase of the game has changed. And now, new changes are coming.
The pick and ban phase of every game goes the same, in League of Legends, except for pro play. While in the SoloQ Ranked games, players pick and ban their own champions all at once, in pro games, as well as in Clash, that privilege is given to the team captain.
The current pick and ban system in any Riot Games LoL tournament works by banning three champions on each side, then picking three champions as well, and then banning two more, before rounding up the final two picks.
However, the League of Legends meta is prominent in these championships, leading to games that feature the same champions over and over again. The LDL, the League of Legends Development League, which is the secondary league in China and features 24 teams: 17 academy teams and 7 independent teams, is implementing a new pick and ban phase called "Fearless Call".
This is a system that works on formats that still use the best out of three games, where teams can only pick each champion once in those three games.
That means that, should a team pick Zeri in one game, they cannot pick it during the next one, but the opposing team can. ANd it applies to all 10 champions picked during a match.
It's a system meant to bring more variety to professional matches, with team compositions not relying on certain champions only. It's unfortunate that it will not catch on in most LoL leagues, as they've abandoned the best out of three system.
However, if it proves a good thing for the eSport, something similar may be developed further down the line, who knows!