The Blues take a 1-0 lead to Stamford Bridge following last week’s 1-0 victory in Prague as the west Londoners look to book their place in the last 16 of the competition.
Chelsea, who sealed their spot in the FA Cup fifth round with a 4-0 thrashing of Brentford at the weekend, have now won their last three games in all competitions.
“We have a lot of confidence and the good thing is that there’s competition between the players, that’s important, especially if you play twice a week,” said Benítez.
“We have more competition now, which is a problem, but it’s good for me. It’s good because we have so many games and it’s important to have the whole squad available.
“I’m quite positive, we’ve scored a lot of goals over the course of the season and we’ve been strong in defence.
“We have to win tomorrow, progress in the competition and then we have tough games ahead. The tournament is difficult; you can see that by the names left in.”
• Chelsea have played fewer games in the Uefa Cup and Europa League than any of the other sides in the round of 32, barring European debutants Levante UD – both sides have played nine games each.
• Sparta have not won in six games in England (D1 L5) since a 3-2 win at Watford in the 1983-84 Uefa Cup third round. They have also not won in their last four European away games, though three of those matches ended in draws.
• Chelsea are within two goals of scoring their 300th in Uefa club competition, while the next one they concede will be the 150th they have let in. This is their 175th Uefa game.
• Chelsea could become the first side to win Uefa’s two top club competitions in reverse order in successive seasons.
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