Van Gaal vs Klopp history doesn't bode too well for Man United's manager
Manchester United vs. Liverpool is not the only clash in which Louis van Gaal and Jurgen Klopp have faced each other. The two managers went head to head in the Bundesliga, with the Dutchman in charge of Bayern Munich and the German leading Borussia Dortmund.
There were four meetings from 2009 to '11: Van Gaal triumphed in the first two -- 5-1 away and 3-1 at home -- but Klopp swung the momentum his way by the end, winning the last two games 2-0 at home then 3-1 away. As the pair try to out-think each other again in Thursday's Europa League clash, what lessons were there from their meetings back in Germany? Here are five things we learned ...
Van Gaal trusted youth against Klopp
The United manager has thrown rookies into his side this season. In his news conference on Wednesday morning, Van Gaal said he will pick "the strongest lineup" but he has shown that he is not afraid of throwing in a youngster during a big game against Klopp.
When Van Gaal and Klopp went up against each other for the first time in Germany, Van Gaal brought on a 19-year-old at half-time. His name was Thomas Muller; he scored a late double. When Marcus Rashford made an early impact for United, Van Gaal said afterwards that it brought back memories of Muller.
Klopp's press paid off
United defender Chris Smalling said in his news conference on Wednesday that a frantic start can be expected for the first 20 minutes on Thursday night. The history of Klopp vs. Van Gaal suggests that could be right -- and it does not make for pleasant viewing for United fans. Klopp's men, deploying their gegenpress, scored in the first 10 minutes in three out of his four meetings against Van Gaal in Germany.
Van Gaal has made wrong decisions against that style in the past, including bringing on Martin Demichelis in the sides' third meeting. The Argentine defender/holding midfielder was a key contributor to the defeat.
Van Gaal's caution caused problems
It has been a familiar scenario for United fans: listening to how their team has dominated possession but failed to score enough goals. Klopp has successfully exposed Van Gaal in the past with smash-and-grab tactics when the Bayern manager has failed to produce a high-tempo game plan for his players.
In their final meeting, Dortmund had arrived in Munich without a win there in almost two decades but then succeeded with that approach. Van Gaal complained at the end: "We dominated but we did not score. Dortmund didn't have any chances but the first shot on goal goes in."
Klopp has tried the unorthodox
When Klopp went into battle against Van Gaal for the first time with Dortmund, he sprung a surprise straight away. He went for a 4-3-3 formation, which the Dutchman admitted he was not expecting, even going as far as saying they were "not prepared for it." It caused Bayern initial problems although their greater quality shone through later in the match.
At the time, Dortmund had just finished outside the European places the previous season but they stormed out of the blocks. It showed Klopp's fearlessness in trying to out-think his opponent.
There was mutual respect
Van Gaal spoke about Liverpool being viewed as an opponent rather than an enemy in Wednesday's news conference. That seems to be the same way he viewed Klopp during their days in Germany, despite the fact that Bayern and Borussia Dortmund were two successful clubs battling each other. The managers' views after the 3-1 win for Munich - which was the club's second meeting - indicated that.
Stephan Uersfeld, ESPN FC's Bundesliga correspondent, says "Listening to the presser again, you can hear the respect both had for each other."
Uersfeld looks back on the four meetings of the two managers and felt that they reflected "one coach on the up and the other on a long way down." At United, Van Gaal's downward spiral has put his position in doubt - meaning that he will be desperate to overcome Klopp, who is still being treated patiently despite an inconsistent start as Liverpool's manager.
There have been moments to savour for Klopp already, as Uersfeld recalls. "The last meeting saw Klopp lose his glasses [celebrating]. After Dortmund had won, he stormed toward his team. [Nuri] Sahin, who scored a screamer during the match, hit Klopp's glasses. They broke. He had a plaster and new glasses for the presser, and his old glasses are now part of the Borussia Dortmund club museum.
"The match was a late Van Gaal classic. Bayern had the possession, made too many mistakes, Dortmund scored the goals."
The challenge now is for Van Gaal to avoid repeating those bad experiences.
Arindam is ESPN FC's Manchester United correspondent. Follow him on Twitter @ARejSport.