Liverpool coach Jurgen Klopp admitted on Tuesday he is impressed with the way Jose Mourinho has recovered from his Manchester United misery to turn Tottenham into genuine title contenders.
Klopp will pit his wits against Mourinho on Wednesday when Premier League leaders Spurs visit second placed Liverpool in a blockbuster showdown.
Two years after Liverpool beat United to trigger the end of Mourinho's disappointing spell at Old Trafford, the Portuguese boss appears to have rediscovered his mojo.
And Mourinho's ability to drag Tottenham into contention for the title just over a year after replacing the sacked Mauricio Pochettino has caught Klopp's eye.
Many pundits claimed the two-time Champions League winner was a fading force after his United sacking, but Klopp never wrote off the former Chelsea, Real Madrid, Inter Milan and Porto boss.
"I am not surprised because that is the world we are living in," Klopp told reporters.
"You are very successful until yesterday probably and if you don't prove it today then people go for you. That's how it is.
"I don't think he was surprised but he showed comeback - if it was a comeback I don't know - skills. Very impressive.
"Very impressive what he did now at Tottenham. The way they play is really good. He turned them into a result machine."
Liverpool remain firmly in the hunt to ruin Tottenham's unexpected challenge for a first English title since 1961.
The champions are behind the north London club on goal difference and would replace them at the top with a victory.
Klopp's main issue is an ever-growing injury list including Virgil Van Dijk, Joe Gomez, Thiago Alcantara, Diogo Jota and Kostas Tsimikas.
Reds centre-back Joel Matip is also a doubt for the game, with club physios working on a back spasm which forced him off during the draw at Fulham last weekend.
If Matip is out, that would leave Klopp without a fit senior centre-back as he tries to subdue in-form Tottenham stars Harry Kane and Son Heung-min.
Between them, England striker Kane and South Korea forward Son have scored 19 goals and provided 14 assists in the Premier League this term.
Tottenham also boast the Premier League's best defensive record this season, having conceded just 10 goals in 12 games.
"Unfortunately, if we keep Kane and Son quiet, they still have a lot of really good players with threats from a lot of areas on the pitch," Klopp said.
"Steven Bergwijn plays an important role in counter-attacking moments. Tanguy Ndombele needed a bit longer to settle at Tottenham, but he's now 100 percent there.
"Giovani lo Celso, Moussa Sissoko, Pierre-Emile Hojbjerg is a proper unit in midfield. It works well together."
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