"Cahill is out due to a problem with his Achilles tendon", Sarri said in his pre-match press conference.
Chelsea now have just two fit centre-backs, although full-back Cesar Azpilicueta can cover there.
His absence is likely to provide an opportunity for Andreas Christensen to start alongside David Luiz, while opening the door for club captain Gary Cahill - who has not made a competitive appearance since November - to return to the bench. "We are in trouble with the centre-backs", said Sarri. "We were lucky previously but not in the last 10 days". "When he sucks players in, that gives me and N'Golo (Kante) space to turn and run at the defence or get a pass off".
Kepa Arrizabalaga continues in goal for the Blues against Eintracht Frankfurt, but there are a couple of changes in the backline shielding him, one of which is enforced.
"Now we control all games and they criticise us because they don't think we win games with possession".
'We want to go to the final but we know very well we'll have to play a very good match next week'.
Fed keeps interest rates steady, citing muted inflation
On Monday, the government reported that the Fed's preferred inflation gauge rose just 1.5% in March from 12 months earlier. One factor in that dovish view is that the economy might not be quite as robust as the latest economic figures suggest.
The Gunners can also qualify for Champions League football via a top-four finish in the Premier League.
- Arsenal & Chelsea are in action in the Europa League semis with the hope of playing in the Champions League next season.
But Eintracht Frankfurt, now fourth in the Bundesliga, are unbeaten in 11 home games in the Europa League, winning nine of them.
The goal was the 21-year-old's ninth of the competition and 26th this season, but Frankfurt failed to press home their advantage, running out of energy in a second half dominated by the visitors. Rudiger is out for at least three months I think.
"They are a very dynamic team, with a great intensity".
"They're really very risky at home, but also away".