Manchester City were enjoying an extraordinary first summer under Manuel Pellegrini, with the dressing room atmosphere fixed and world-class players arriving in steady supply.
Txiki Begiristain has lead a perfect recruitment drive, and while they may have overpaid for their new stars, they will undoubtedly add the quality and depth needed to run a dual assault on the Premier League and UEFA Champions League this summer.
Jesus Navas adds the width they've been crying out for for three years, Fernandinho adds mobility and stability in midfield and the Stevan Jovetic-Alvaro Negredo combination can be prolific.
It was verging on the ideal summer...until City let Denis Suarez go.
The club were in a tight situation, with Barcelona's overtures holding considerable power and enticement for the young Spanish midfielder. The Catalan giants had already tried to nab him once, as according to The Daily Mail, City beat off their interest initially to sign him in 2011.
He has been the most promising prospect in the Citizens' Elite Development Squad for several seasons, and in 2012 won the club's Young Player of the Year Award.
But first-team football has been almost non-existent, and after starring at the FIFA U20 World Cup alongside the likes of Oli Torres, Gerard Deulofeu and Jese Rodriguez, it seems competitive football is on his agenda and at Barca he can find it.
The tournament in Turkey proved a marker for his (lack of) progress, as while Suarez was expected to shine, it was the little-known Oliver who stole the show in the centre of La Rojita's system.
Why? The diminutive pass-master played the 2012-13 season with Atletico B (23 appearances, three goals) and has made eight appearances in Diego Simeone's first team as a result.
Suarez will now slot straight into Barca B, but that doesn't mean he'll be subjected to reserve treatment all over again. Barca B play in the Segunda division—the second tier, an equivalent to the English Championship—and he'll be gearing up to play against the likes of Real Zaragoza, Mallorca and Tenerife this season.
He stands to play alongside the likes of Jean Marie Dongou, Sergi Samper and Frank Bagnack, but perhaps most importantly of all, he is widely seen as Xavi's natural successor.
The first heir to the throne, Thiago Alcantara, has gone, and therefore Els Blaugrana's plans to link he and Cesc Fabregas for eight or more beautiful years has been scuppered.
Suarez is one hell of a reserve option, and while City fans will be delighted they recouped a fair chunk of cash in a forward-thinking transfer, this has to be seen as a bitter blow.
City's relentless pursuit of two world-class players per position—in order to ensure they do not fail on the European stage once again—has pushed their very best youngster out of the door.
The potential to rake in £8.4 million is a cushion, but it doesn't make up for the loss of a player who Barca coaches believe will emulate the mighty Xavi.
It's the first bad move of the window so far, and it's Pellegrini's first notable mistake in charge of the club. How much control he had over it was unclear, but it was City's buying big that forced Suarez's hand and left him feeling disillusioned.