Mkhitaryan was cup-tied as the Gunners came from behind to beat their London rivals 2-1 and set-up a Wembley date with Manchester City on February 25.
After a goalless first leg, Chelsea struck first at the Emirates Stadium as Eden Hazard gave them an early lead.
But an Antonio Rudiger own goal drew the hosts level before Granit Xhaka’s winner on the hour-mark saw Arsenal seal a first League Cup final in seven years.
Sanchez’s future had been up in the air for some months as it became increasingly clear he would not sign a new deal at Arsenal.
After a summer move to Manchester City failed to materialise he instead ended up moving to United and Wenger believes the destabilising effect of not knowing what would happen with Sanchez was lifted in time to see off Chelsea.
“It’s a great, satisfying night for us because we managed to beat a strong team and I felt that in January we paid a heavy price for uncertainty that was existing in our dressing room,” he said.
“Now we are back with more clarity, we know what we have to do and we can focus on our game and so we had difficult months, but we responded well.”
Wenger has never won the League Cup during his 21-year reign as Arsenal boss and saw his side shocked in the 2011 by Birmingham.
“It is unfinished business yes, because we didn’t win, but we are again at Wembley and many times we were there, but we are in the final again and we can take our fans there,” he added.
“That’s what you want, but of course now we are in it we want to win it and we will play against a very strong side, so it could become a very interesting game.”
— Arsenal FC (@Arsenal) January 24, 2018
Chelsea will now turn their attention to the FA Cup as they continue to be linked with a move for Roma’s former Manchester City striker Edin Dzeko.
The reigning Premier League champions lacked a cutting edge as they looked to get back into the contest on Wednesday night as manager Antonio Conte once again spoke of the club’s recruitment process.
“I think the club decide our transfer market,” he said.
“My task is to try and improve the team, about the transfer market from the summer, the club decides every single player.
“I think there are different situations, sometimes I can have an impact on the transfer market but sometimes I don’t have an impact on this.”
Provided by Press Association Sport
Following a goalless draw at Stamford Bridge in the first leg of the semi-final, an Antonio Rudiger own goal and Granit Xhaka strike saw the hosts seal victory after Eden Hazard’s opener.
Here, we look at three things learned from the encounter.
HAZARD NEEDS A PARTNER IN CRIME
Simply put, Hazard did not deserve to end up on the losing side. He’s been playing wonderfully for Chelsea this season, even when results haven’t gone their way and it was much of the same story again on Wednesday night.
He was the one who made the breakthrough with a darting run that caught Arsenal’s centre-backs on their heels before slotting his finish away expertly.
The Belgian was a constant threat, drawing a total of five fouls over the 90 minutes and creating a plethora for chances for his team-mates.
Unfortunately, no player in blue was able to rise to his level on the night, especially with Willian having to go off injured before the half-hour mark and his replacement Ross Barkley making an underwhelming debut.
With Alvaro Morata proving to be a bit hit and miss this season as well, Hazard is desperate for an attacking team-mate of the quality and finishing ability to compliment him.
WILSHERE DESERVESWORLD CUP SPOT
Once again, Jack Wilshere put in another fantastic, energetic display in Arsenal’s midfield. There’s no question that he was the best player for the hosts on the night.
He’s renowned for his ability to drive forward from midfield with the ball and on this occasion even managed to upstage Hazard in that department, registering six assists to the Belgian’s five.
His passing was on point as well, rarely giving away possession and in fact being integral to his side’s build-up play.
Wilshere has brought a new level of dynamism to Arsenal’s midfield, despite only recently returning from a lengthy injury lay-off. On this form, who can deny him a spot in England’s World Cup squad?
WENGER GETS THE BETTER OF CONTE
Arsene Wenger took a severely depleted squad to Stamford Bridge in the first leg but his players must be credited for battling to a 0-0 draw.
Antonio Conte on the other hand has now paid the price for not being more adventurous when the Gunners were there for the taking.
Granted, both of Arsenal’s goals had a bit of fortune about them as the hosts benefited from some telling deflections. However, they were definitely the better team overall.
Wenger’s decision to ask Mohammed Elneny to drop deeper in the second half paid off as Chelsea were unable to create many chances of note while it also freed up the likes of Wilshere and Granit Xhaka to join in the attack.
Over the two legs, it has to be said that the Arsenal boss played his cards well.