Liam Rosenior has only lost one game since taking the job at Stamford Bridge and there have been positive signs that his side are developing.
They pulled off a second half comeback to turn around a 2-0 half time scoreline and go on to beat West Ham 3-2 in the Premier League at the weekend. Rosenior will be pleased that his half time substitutions had an impact, as Joao Pedro scored and registered an assist, whilst Marc Cucurella also grabbed a goal.
Much has been made of the size of **Chelsea's**squad and the players that they have available. Strength in depth is something that every manager finds for and **Chelsea**will be wanting to show that more often.
That is because Alejandro Garnacho was the hero from the bench in the first leg of the cup semi-final as he scored twice but had a poor game from the start on Saturday. He will be hoping that this competition allows him again to make an impact and help his search for consistency and a regular spot in the line-up.
Jamie Gittens had to be withdrawn due to injury against West Ham in the first half, but he was another who had a difficult game and has struggled to make too much of an impact at times this season.
Who starts?
It will be of interest to see who Liam Rosenior gives starts to at the Emirates Stadium this week. At 3-2, they are very much still in the tie and the first goal could be key.
Therefore, it could be expected that Rosenior starts with his strongest eleven and has players who can come off the bench and make an impact if required.
For the West Ham game, there was seven changes to the side that qualified to the next round in Europe after another 3-2 win at Napoli.
Particularly at the back, it will be important that the Blues make a good start and do not let the game get away from them before they are able to create chances of their own.
A tough test
So far, Chelsea have climbed to fifth and are well in with a shout of playing in the UEFA Champions League next season. Qualification for that tournament will be a priority.
However, they have a chance of making a cup final and that could provide a welcome boost to their season.
Arsenal have the lead and are at home but Chelsea will feel confident that they can still progress.
In the first leg, after getting back into the game after conceding an early goal, they came away with a lot of credit. That was even with making some defensive errors that night.
It was also Rosenior's second game in charge and he has now had more time to get his messages across to the players.
It could be argued that this is the toughest match Rosenior will have had in charge of the club so far. He will not be judged on this game alone but will want his side to give a good account of themselves.
After back-to-back 3-2 victories in their last two games, Rosenior will have learnt a lot about his side but he may also be hoping that they can tighten up at the back and not concede so many.
Arsenal pose a threat from set pieces so his side will have to be resolute and well organised if they are to keep a clean sheet.
However, until a win against Leeds United at the weekend, the Gunners had suffered a home defeat and had consecutive 0-0 draws. They were unbeaten at home until the defeat to Manchester United. Those recent results may just give Chelsea some extra confidence as they make their way across the capital.