Hakim Ziyech strikes early in the second half to take the Blues to Wembley.
It was a game of conservative and careful play from both sides. Manchester City's hope of making a quadruple swoop of titles was ended on Saturday night as Tuchel's side showed why they should be at Wembley for the final.
Before the game, it was all about Manchester City making it to the Finals and clinching the title to gain total dominance of the English league.
This is the first time Thomas Tuchel will be having the edge over Pep Guardiola, having met each other in the German Bundesliga several times and the Spanish having the edge over Tuchel.
Tuchel has made a big impact at Chelsea, coming in this January, playing 19 matches and losing just 2 matches out of the 19. He is in the Semi-Finals of the UEFA Champions League and just qualified for the FA cup final. Having to make different tactical tweaks to ensure Chelsea has a good run. Tuchel had said earlier that Chelsea needs to hunt City next season.
The German said, "If you have good ball possession against City, maybe it is the best way to defend. We are very strong in the numbers in the defensive statistics. It belongs to the courage of the players. The individual behaviour and as a team,
"We defend very, very actively and aggressively with huge solidarity. This is the key. On this level, it is like this. Everyone needs to attack and defend."
Timo Werner bursting on the attack, after being played through by Mason Mount, who have been resounding for the blues side this season, Werner laid the ball in the path of the running Hakim Ziyech, who made no mistake in putting the ball into the net.
Manchester City suffered a blow when Kevin De Bruyne was subbed off, after looking to have picked up a knock. He came off for City's Champions League hero, Phil Foden. The England star made a good impression as he came on, but Chelsea's tactics was more than too much for him, having silenced Raheem Sterling and co for most of the match.
Chelsea will now face the winner between Leicester City and Southampton.