The World Cup is not only football's biggest tournament, but it also serves as a shop window for players to impress onlooking clubs.
Jose Mourinho's first season back at Chelsea ended in disappointment as the Blues failed to land a trophy, but fans can be confident that they will mount a title challenge next season having come so close this time around. Mourinho will now be planning a summer of spending in order to get Chelsea over the finish line, and some World Cup stars may be of interest.
With central midfielders and strikers needed at Stamford Bridge, you can be sure that Mourinho will be bringing some new faces in to fill those holes, whilst depth could also be added to the defence. With that in mind, here are five stars playing in Group B at this summer's World Cup that could fit the bill.
Alberto Moreno, Spain
The confusion surrounding the future of Chelsea left back Ashley Cole means the Blues could well be looking for a new left back this summer, and whilst there have been strong links towards Southampton youngster Luke Shaw, it's Sevilla's Moreno who has been most talked about lately. The 21-year-old should travel to Brazil as a backup to Jordi Alba but Mourinho will be keen to see how he copes on the world's biggest stage in limited playing time.
Diego Costa, Spain
Chelsea are trying to push through a deal to sign Costa before the tournament gets underway, and even if they do then Blues fans will be keen to watch their new man in action. The Brazilian-turned-Spaniard has enjoyed a sensational season with Atletico Madrid but many want to see whether he is just a one season wonder, and spearheading the Spanish attack will go a long way to proving those doubters wrong.
Wesley Sneijder, Holland
Despite having a number of playmakers already at Stamford Bridge with the likes of Eden Hazard, Oscar, William and Andre Schurrle, Chelsea have been continuously linked with a swoop for Sneijder since Mourinho came back to the club. After all, the 29-year-old Galatasaray midfielder was a favourite of Mourinho's during their time together at Inter Milan, and there is little doubt that both parties would be happy to reunite - the only question would be where does he fit in?
Arturo Vidal, Chile
One of the problem areas for Chelsea is finding a natural partner for Nemanja Matic in front of the back four, and with Frank Lampard ageing, John Obi Mikel rumoured to be leaving and Ramires having a disappointing season, Mourinho may choose to splash the cash again. Juventus star Vidal has established himself as one of the top midfielders in Europe in recent years, and having scored 18 goals this season, he will be the driving force for Chile - which could tempt Mourinho into a bid.
Alexis Sanchez, Chile
Recent speculation has linked former Udinese star Sanchez with a move to Stamford Bridge in a part exchange deal which would see Blues defender David Luiz head to Barcelona in return. The Chilean international offers pace, direction and goals, but would surely only be a Chelsea target if he was considered a striker - or if Eden Hazard departs the club this summer.