For Pep Guardiola, all roads lead back to his beloved Catalonia. He is seeking a response to his first setback at Manchester City, inflicted by Tottenham's former Espanyol manager Mauricio Pochettino.
Now he faces a battle of wits with an old Barcelona team-mate, Ronald Koeman. And on Wednesday, he returns to the Nou Camp in the Champions League.
Perhaps the deserved defeat at White Hart Lane will prove the first of a trilogy of disappointment for Guardiola. The challenge for him is to illustrate that it is a one-off and that City can overcome teams adopting increasingly familiar tactics.
Celtic and Spurs have played high-pressing games, looking to put City defenders under pressure. The astute Koeman will surely follow suit.
In particular, City's last two opponents have highlighted their problems in the full-back positions. With Bacary Sagna sidelined, Everton must aim to do likewise.
That requires a change of tactics. Koeman used a midfield diamond in the recent draw with Crystal Palace two weeks ago.
A reversion to 4-2-3-1 would mean restoring wingers. Yannick Bolasie and Kevin Mirallas, like striker Romelu Lukaku, are not renowned for their defensive work, but Koeman must persuade them to hassle and harry the City rearguard.
For his part, Guardiola will surely demote Jesus Navas and Fernando, two players he inherited and substituted at Spurs.
It helps that Nolito has completed a three-match ban. Ilkay Gundogan could return in midfield, whether or not the game comes too soon for Kevin de Bruyne.
With Lukaku, Leighton Baines and Phil Jagielka fit, Everton's injury worries are over. They may also benefit from Koeman's inside knowledge of Guardiola's thinking, even if understanding what his old friend will do is no guarantee he can stop him.
But both were disciples of the late Johan Cruyff at Barcelona and have brought inventive thinking to their managerial duties.
Koeman's time at Southampton showed he is capable of overcoming the elite in one-off meetings; he earned the Saints two wins on the other side of Manchester and inflicted Manuel Pellegrini's last league defeat as City manager.
Yet that was not at the Etihad Stadium and Guardiola's team have a 100 per cent home record. On their own turf, tactics that seem to entail fielding an old-fashioned front five can seem less risky.
It is why, in a game of reunions, the crucial old boy may not be John Stones, the defender City paid Everton £47.5 million (S$80.5 million) for, but Gareth Barry, the veteran patrolling the territory where Guardiola can field two No. 10s including David Silva. The Englishman believes City's Spaniard is his greatest ever team-mate.
Lacking pace, relying on his reading of the game, Barry has certain similarities with Guardiola the player. Guardiola the manager is confronting his past this week.
The boy from Barcelona will be tested by old allies.
MANCHESTER CITY V EVERTON
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