With domestic campaigns just days away from conclusion, many teams would be looking at their squad to identify areas the team needs bolstering in.
As the transfer window edges closer day by day, it certainly is an exciting period for fans, who are already licking their lips at the prospect of watching new players join their favourite clubs.
Some clubs though, have already made a mark in the market, signing players a month before the window has swung open. It's a much-required head start and it will help them in enjoying a moment of peace when others are running around to sign the players.
We look at clubs who have signed players before the transfer window opened:
4. Borussia Dortmund
Borussia Dortmund have already acquired the signatures of Borussia Monchengladbach starlet Mahmoud Dahoud and Bayer Leverkusen skipper Omer Toprak.
It would certainly come as an encouragement to the club that they are still a prime destination for clubs, despite the fact that they won't finish above third this season, which is a little disappointing going by their standards.
With manager Thomas Tuchel likely to leave at the end of the season, the new manager will be happy to have two very good players at his disposal.
Tuchel was forced into playing Sven Bender as a central-defender during this season, but the capture of Toprak will make sure that they have a reliable, proper centre-half. Dahoud's hard-working style makes him a player every team would like to have in their squad.
3. AC Milan
The almost-confirmed captures of Ricardo Rodriguez and Franck Kessie shows the intent and ambition of AC Milan's new Chinese owners.
Gianluca di Marzio, one of the most reliable sources on transfer news, has told that they are done deals. The Rossoneri have shelled out a straight sum of €15 million for Rodriguez, with a further €3 million in incentives, apart from spending €28 million on Kessie, who has been a standout performer for Atalanta this season.
Vincenzo Montella would certainly love to have players of their quality in the side, which is likely to qualify for the Europa League next season.
There's no Premier League team who is need of reinforcements more than Arsenal and they've started off early.
News outlets across the world broke news of their capture of Schalke wing-back Sead Kolasinac last week, bringing smiles across the faces of many Gunners fans, despite the club not having commented yet.
The Bosnian has been one of Markus Weinzierl's men best players this season and is known to have a warrior like instinct to his game, which is something that Arsenal need.
The Gunners have been accused of not having any characters in the side and Kolasinac is someone who brings that to the plate, apart from his all-round ability on the left flank.
1. Bayern Munich
Bayern Munich have already pulled off two impressive deals by nabbing two of Hoffenheim's best players before the transfer window actually opened.
Midfielder Sebastian Rudy will arrive for free, while defender Niklas Sule has signed a five-year contract for an undisclosed fee.
The Bavarians have a knack for signing quality youngsters from smaller Bundesliga clubs and they have shown that they still have that quality to a large extent.
Sule happens to be a dominating centre-half, who received his first Germany call-up earlier this year and was linked with Borussia Dortmund last summer. Rudy happens to be a more familiar face, having already represented the German national side multiple times in the past.
The 26-year-old utility man can play right-back, right midfield and central midfield, making him a versatile addition at the Allianz Arena.