For a brief moment in the summer, the careers of Arsene Wenger and Sam Allardyce -- two polar opposite personalities with very distinct philosophies of football -- became professionally entwined for the first time.
It was eventually Allardyce who landed the England job left vacant by Roy Hodgson's departure, but only after Wenger turned down the Football Association and refused to leave Arsenal. After failing to land the longest-serving manager in English football, the FA eventually settled on a man who lasted only one game in the job -- the shortest England reign of all. And once Allardyce was sacked in disgrace, the FA's thoughts again turned to Wenger, but again they were left disappointed.
It is hard to imagine how two men with such contrasting visions of the game were ever part of the process for the same job. Two different sets of criteria must surely have been applied when testing what it was the FA really wanted from a manager if they could flit between the two, and then back again.
But the upshot of England's summer and autumn of tumult is that when he takes charge of Crystal Palace for the second time on New Year's Day, Allardyce will face Wenger on the touchline as the manager of a sixth different Premier League club. Bolton Wanderers, Newcastle United, Blackburn Rovers, West Ham and Sunderland are the others Allardyce has serviced during his top-flight career.
Theirs is a long and at times bitter rivalry. But much of the sting has been drawn out of it. Even during his brief reign as England boss, Allardyce found the time to try and find common ground with a man he once appeared to have made a lifetime enemy of with his agricultural football and antagonistic entreaties. In fact, the process of reconciliation had already been in place for some time.
Contrast the following two statements. In his autobiography, published in 2015, Allardyce wrote of his time with Bolton: "We'd really got to them and Arsene Wenger hated us. ... The more I could wind him up, the more I liked it." Two months later, now Sunderland manager, he said: "I've never thought anything other than, from a professional level, Arsene Wenger is a top manager. ... I think it was just wind-up stuff that we all get up to."
Despite Allardyce's protestations, their interactions were rarely ordinary. Jose Mourinho and Sir Alex Ferguson aside, Allardyce is the manager Wenger has clashed with the most in English football, verbally and stylistically, and this all adds weight to an otherwise quite nondescript London derby which has not seen Arsenal lose at home to Palace since 1994. Indeed, Palace have only one point from a possible 18 against Arsenal since they returned to the top flight in 2013.
Allardyce's chances of ending this run are hampered by the fact he has had so little time to work with his new club, at what is already the busiest juncture of the season. But they were only a Troy Deeney penalty away from winning his first game in charge, away at Watford on Boxing Day, which already signified some improvement.
Wenger, you sense, would always relish a victory against one of his most persistent aggravators, and in this he is aided by the return from injury of Shkodran Mustafi, who has not played since the 3-1 win over Stoke on Dec. 10 and is yet to lose in 17 appearances for the club. His return alongside Laurent Koscielny would add some much-needed quality and assurance to the back line.
Aside from the recent back-to-back defeats to Everton and Manchester City, which both came away from home and so rocked confidence around the club, Arsenal are actually unbeaten at home in the league since losing to Liverpool on the opening day of the season. And if Alan Pardew was still in charge of Palace, this would have the sniff of a routine win about it.
But with Allardyce coming to face down Wenger again, there will be little routine about Sunday's match. It will be impossible to escape their shared history -- both this summer and over the past 20 years -- when they troop out of the tunnel on Jan. 1.