It would be foolish for Yaya Toure to move to Manchester United. Having spent years building a legacy at their cross-town rivals, Manchester City, culminating in an emotional on-the-pitch send-off after the 3-1 win over Brighton earlier in May, the midfielder should note that there are few players that manage to cross the divide and remain loved by the team they're leaving.
Though it would be mildly amusing for City fans to see that it was now United looking for the one-season wonders and top-level cast offs in the way that it used to be City who snapped up aging pros like Andy Cole, Peter Schmeichel or Denis Law. They all had varying degrees of success and few that have played for both sides have actually made the transition direct from one Manchester club to the other.
What's changed since most of the old deals between the clubs, though, is their relative status.
Fans find it hard to get too bothered when a club legend swaps sides in a rivalry if one of the teams is struggling and the other is performing at the top level. (That being said, despite United's second-place finish, one team is operating so far in advance of the other at the moment.) Nevertheless, the rivalry between City and United is at its strongest for some time.
Since the current Premier League champions returned to the top table and began fighting for the top honours again, the intensity of feeling between the sides has increased. It's so much more important when winning and losing on derby day could spell the difference between a trophy or not across a number of competitions.
Toure should remember the send-off he got after the match with Brighton because all that was said was down to what he's done to get the club in the state it's in right now. Without his influence since his arrival in 2010, City's trophy cabinet wouldn't be as stocked as it is now and they wouldn't have transformed into the perennial winners they've become.
Down the years, David Silva was the creative genius who created City's opportunities, Sergio Aguero was the lethal centre-forward who finished off the chances and Toure was the leader who could be relied upon for the big moments when the team needed them most.
The list of such moments is extensive, too: he scored the winner in the 1-0 FA Cup semifinal and final victories over Manchester United and Stoke to earn the club's first trophy of the Sheikh Mansour era. Toure scored twice at Newcastle to turn a tough game into a 2-0 win to set City up for their first Premier League title. He turned a 1-0 deficit around, in City's 3-1 win over Sunderland in the League Cup final in 2014, with a wonderstrike from nothing. Furthermore, his 20 Premier League strikes that year guided his club to another title.
With a list like that to his name, a move to Manchester United would leave fans feeling like he had soured the memories. Toure was the driving force behind elevating City beyond their rivals, so it would be a very bitter pill to swallow to watch him pull on a red jersey and become what would surely be a bit-part player in Jose Mourinho's team.
Supporters have forgiven the Ivory Coast midfielder's misdemeanours in the past. They've put up with his loudmouth agent sounding off to the press on a regular basis, and they've forgotten about the will-he-won't-he transfer speculation that came so frequently with the summer months. But plying his trade at Old Trafford might well be a step too far: it would fly in the face of everything he's achieved at the Etihad and the legacy he's built over the past eight years.
This isn't an aged Law leaving United to score a few goals, including one notable back-heel at Old Trafford in 1974 for City in his final season. This isn't Schmeichel keeping a few clean sheets for Kevin Keegan's newly-promoted side in 2003, either. This is more like Carlos Tevez's Dear John to Sir Alex Ferguson by moving across town to be the start of something special at their nearest rivals.
Of course, Toure isn't young enough to have that influence at Old Trafford but his reputation among City fans wouldn't come out of such a transfer intact.
The midfielder will believe he can perform at the top level still, though his recent performances for City suggest he can't do it on a regular basis. If there is an offer on the table from Mourinho, Toure should think very carefully about his answer after everything positive he's done at the Etihad. After all, the idea of him in red and calling Old Trafford "home" is enough to turn any City fan's stomach.
It's just plain wrong.