In May 2001, Liverpool celebrated a double cup win in a matter of days, winning the FA and UEFA Cups to finish off a season in style. The Reds that season won a cup treble, with the League Cup coming earlier in the campaign, and finished in the top three in the Premiership to win a Champions League spot.
The stage was set for the Reds to improve during the summer and take another step toward the ultimate aim of finally picking up a Premier League trophy.
Manager Gerard Houllier brought in two goalkeepers, Jerzy Dudek and Chris Kirkland, to strengthen that area of the team, as well as young forward Milan Baros and left-back John Arne Riise. The only notable exit from the first team squad was Christian Ziege during the summer, though a few others left during the course of the season too, including Sander Westerveld and Jamie Redknapp.
There was one other sale, in November of 2001, which was of huge relevance: the departure of Kop legend Robbie Fowler, who left for Leeds United after not being considered a first-choice striker.
Though Emile Heskey and Michael Owen were providing goals the Reds needed another forward, and Houllier turned to the loan market to capture compatriot Nicolas Anelka from Paris St. Germain.
Liverpool saw out the season in some style, finishing second in the league and reaching the Champions League quarterfinals, where they lost against Bayer Leverkusen.
In truth the campaign could have been even better, but after an emotional season where Houllier suffered severe health problems and assistant Phil Thompson had to look after the team for a spell, it was generally seen as a year where Liverpool had progressed once more.
Liverpool looked ready to mount a serious title challenge, at long last.
The end of the 2001-02 season saw the Reds win nine of their last 11 games, with just defeats against Leverkusen and, in the league itself, against Tottenham Hotspur.
The Reds hit 13 goals in their last four league games at Anfield, with Anelka playing a prominent role as a striker alongside Owen.
Heskey was moved out to the left flank at times, while other games saw Anelka in a withdrawn role, or either of the two entering the game from the bench.
Supplied and aided by the two taller strikers, Owen scored four times in those last four games, while Anelka helped himself to a couple as well. He ended his loan spell with 22 appearances in all competitions, five goals, and he looked completely at home in the red shirt, playing at Anfield and playing in a team which attacked at pace.
Liverpool finished seven points behind Arsenal and it was imperative that the club get their summer signings right to make the biggest step up of all—from second to first.
Anelka should have been a shoo-in to secure on a permanent deal, but Houllier had other ideas.
Instead, he was allowed to join Manchester City, while Liverpool chose to bring in Lens forward El-Hadji Diouf for around £10 million. Fellow France-based duo Bruno Cheyrou and Salif Diao joined the club that summer, as well as Patrice Luzi and Alou Diarra on free transfers.
All five were spectacular failures for Liverpool.
Diouf in particular, as Anelka's replacement, Liverpool's No. 9 and the most expensive signing, was a complete disaster.
Aside from not displaying the technical or physical attributes that had made Anelka such a success, Diouf also displayed an insufferable attitude on the pitch, and scored a paltry six goals from 47 appearances in his debut campaign. He missed penalties, bickered with teammates, was shunted out to the right wing after failing to provide a goalscoring edge to the team and eventually lost his place.
The only surprise was that he was allowed to continue at the club for a further season before being shipped out on loan and finally sold.
Cheyrou was also an unqualified disaster after displaying a shocking lack of work rate, pace or stamina, despite having good technical ability, and he drifted from a central position to the wing before leaving the starting XI entirely. Diao was the most honest of the lot; he worked hard and brought some power to midfield, but lacked entirely in the technical attributes side of his game.
Luzi and Diarra managed a single senior appearance off the bench for Liverpool between them.
With Nick Barmby and Jari Litmanen leaving the club in the summer of 2002, as well as Anelka, Liverpool completely failed to restore and upgrade their attacking options in the team.
Meanwhile, Anelka scored 14 goals that season for Manchester City, in a team who finished below the Reds in the table.
Liverpool ended the 2002-03 campaign in just fifth place, far worse off than the previous season and 16 points down on their last year's total. The Reds had gotten it badly wrong in the transfer market at the crucial time and it didn't just cost them a shot at the title that season, but also in the years to come.
Houllier's team fell apart after that, and that fifth-place finish marked the beginning of the end for the Frenchman in charge.
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The squad, especially the attack, needed to be reconstructed once again, and Liverpool were back in rebuild mode. Within a year, Houllier was gone, Rafa Benitez was in place and a new transition phase was upon the club.
Glory has followed in Europe and the FA and League Cups since then, as well as one real tilt at the Premiership title in 2009, but ultimate domestic domination continues to elude the club.
Had Houllier and his management team opted for the proven quality and impact of Anelka over Diouf, and perhaps another key element was added to the side back in '02, perhaps things would have turned out very differently for Liverpool that season and beyond.
Stats and historical data from LFCHistory.net