Atletico enjoyed a stunning season under Diego Simeone last term, winning their first La Liga title in nearly 20 years before losing the Champions League final to cross-city rivals Real Madrid. Their success has made La Liga a three-horse race again, and the club are still well placed to challenge next season despite the departures of key players such as Thibaut Courtois, Filipe Luis and Diego Costa.
All three will be turning out for Chelsea next season, and Atletico have already moved to replace the trio. Benfica goalkeeper Jan Oblak has arrived to take Courtois' place, whilst Bayern Munich striker Mario Mandzukic will be looking to replicate Costa's success last season, as the Spanish international hit 35 goals in all competitions.
At left back, Granada's Guilherme Siquiera has joined as a replacement for Luis, but the club are still looking to add another option there. They are notably interested in signing Zenit St. Petersburg's Cristian Ansaldi, and this all but confirms that former Liverpool left back Emiliano Insua will be leaving the club.
That notion is supported by the speculation today linking Atletico with a double swoop on Arsenal for playmaker Santi Cazorla and left back Monreal. Their pursuit of Monreal is particularly interesting given that Arsenal are short in defence already, and allowing another one to leave could make Arsene Wenger's job in the transfer market slightly more difficult.
The 28-year-old arrived from Malaga back in January 2013, but has mostly been playing second fiddle to Kieran Gibbs in the Arsenal defence. Just 13 Premier League starts last season killed off any change of him making it into Spain's World Cup squad, and maybe he realises that a move back to Spain is the only way to further his career.
Whether Arsenal would let him leave - particularly with another deputy left back set to depart in Thomas Vermaelen - remains to be seen. Yet what we do know is that Gibbs is the clear first choice for now, and in the future too, meaning Monreal's prospects ahead of the new season don't look good.