The Gunners boast a 3-2 lead following the first leg meeting at Stamford Bridge last month and enter the game attempting to defend their advantage as they seek to make it to the final.
Arteta’s side sit top of the Premier League, finished top of the Champions League league-phase table, are into the fourth round of the FA Cup as they compete on all fronts this season.
Merino's injury is a big blow
The Spanish head coach first spoke on Mikel Merino, who will undergo surgery this week after suffering a fractured foot.
Is it a fracture: “yes.”
Will he be back before the season ends: “Let's see. It's a very rare injury, so we have to wait and see once we have the surgery. How that reacts daily.
“Obviously, he needs to go through a procedure, which is never always positive. He's a big player for us. An athlete that has such a versatility and capacity to compete in various positions. Yeah, that's a big blow.”
Merino to be replaced today?
Questions then turned to replacing Merino, something Arteta says will not happen unless he and his team can find a quality replacement as he refuses to give in to panic buying before the window shuts.
"I wouldn't say relaxed, I think we are on it, and it's our responsibility, when we are playing for what we are playing, to give ourselves the best opportunity and chance to look at the market, every option, evaluate them, and then make a decision whether we do something, if it's possible.
"I mean, when you lose a big player like this in the squad with four months to go and all the competitions to play for, you need to look and we need to do everything that we possibly can to see if we have a player that is available.
"And if we don't, we keep what we have."
Finally, Arsenal beat Leeds United 4-0 at the weekend, extending their lead at the top of the table to 6 points. Arteta was asked if this weekend feels like his side have won the title, a question he shrugged off with so much of the season to go.
"Yeah, we need another 13 or 14 of those and that will make it happen. So, we know how much is still to do. We are very conscious of that. I think every club is very conscious of that."