Maurizio Sarri faces a centre-back dilemma as Chelsea take on Eintracht Frankfurt in the first leg of their Europa League semi-final.
Gary Cahill has been left out of Chelsea's 19-man squad due to an Achilles injury. The centre-back has not featured for the first team since November with Antonio Rudiger also out for the rest of the season following knee surgery.
Andreas Christensen and David Luiz are the only recognised centre-backs in the squad, although Chelsea have been training with Cesar Azpilicueta in the position.
Sarri said: "We are in trouble with the centre-backs... We've played 58 matches so injuries are typical. We were lucky previously but not in the last 10 days.
"I respect Frankfurt. They have played against big teams and are a dynamic side with great intensity, and physically they have the same characteristics as [quarter-final opponents] Slavia Prague, but the quality is better, especially in attack. It will be difficult to get to the final."
Eintracht Frankfurt manager Adi Hutter says he side will need to be at their best if they are to beat a strong Chelsea team.
He said: "It is important that we also enjoy this game. We are playing a semi-final, against such a big club. This is something special. It is important that we also enjoy this game. We are playing a semi-final, against such a big club. This is something special."
Team news
Elsewhere for Chelsea, Willian had picked up a heavy knock against Manchester United at the weekend, but will be ready to feature in Germany.
Eintracht Frankfurt will be without the banned Ante Rebic, but Evan Ndicka does return after his own ban.
Sebastien Haller will also miss out due to an abdominal issue, and Mijat Gacinovic looks set to be involved having previously suffered a stomach injury.
Opta stats
- This is Eintracht Frankfurt's first European semi-final since 1979/80, when they ultimately won the UEFA Cup after defeating Bayern Munich and Borussia Mönchengladbach in the semi-finals and finals respectively.
- This will be Chelsea's ninth major European semi-final appearance in the Abramovich era (since 2003/04); no club has appeared in more since then (Barcelona also nine).
- These two sides have never previously faced off; Eintracht have lost at home to English opposition just once before in all European competitions - 0-1 vs Nottingham Forest in the Inter-Cities Fairs Cup in 1967/68.
- Chelsea have lost just one of their last 10 games against German sides in all European competitions (W5 D4), and have won their last two such games in Germany, both versus Schalke in 2013/14 and 2014/15.
- Eintracht have played 10 Europa League games at the Commerzbank-Arena, winning eight times and drawing twice; they haven't trailed for a single minute in those games.
- Chelsea manager Maurizio Sarri is unbeaten in his last 13 games in the Europa League (W12 D1). The only manager to go on a longer run without defeat since the competition was rebranded in 2009/10 is Jürgen Klopp - 14 games (W6 D8) with Borussia Dortmund and Liverpool between October 2010 and April 2016.
Charlie's prediction
This is a tough game to predict. Frankfurt are doing well, they had a big comeback in the quarter-finals and will be looking at the key to Chelsea, which is Eden Hazard of course. They will sit back - German teams have a good structure - but Hazard can blow that structure away and is key to what Chelsea do.
Chelsea will try and play on the counter-attack - I hope Maurizio Sarri doesn't play Hazard as a number nine. He is easier to mark and harder to get the ball to. Marcos Alonso is definitely vulnerable when he plays left-back, so I am looking at a slight defeat for Chelsea that will leave them with work to do before next week's return at Stamford Bridge.
CHARLIE PREDICTS: Frankfurt 2-1 Chelsea (9/1 with Sky Bet)
When is the Europa League final?
The Europa League final, the 10th in its current format and 48th overall of Europe's second-tier competition, will take place on May 29, 2019.
Kick-off is at 8pm (BST), 9pm (CEST).