According to Gianluca Di Marzio, Madrid are not willing to pay the Serie A side's asking price for their star stopper, giving Chelsea the edge in the chase for the Brazil international.
The move would likely push Courtois closer to the Stamford Bridge exit door. The Belgium international reportedly won't sign a new contract with the Premier League side, and his deal is set to expire in 2019.
Alisson enjoyed a breakthrough campaign in 2017-18, cementing his place as Roma's starting goalkeeper and excelling under manager Eusebio Di Francesco.
Journalist David Amoyal believes Alisson would be a fine signing for the Blues, especially if former Napoli coach Maurizio Sarri does take over from Antonio Conte as manager:
The aforementioned price would be a world-record fee for a goalkeeper, although based on how he performed last term it's tough to argue with Roma having such a high valuation.
Alisson's basic goalkeeping skills are outstanding. Since becoming Roma's starting goalkeeper in 2017, he's showcased razor-sharp reflexes, a command of his penalty area and exceptional composure in one-on-one situations. The 25-year-old is also agile enough to produce stunning saves.
The goalkeeper's excellent distribution gives him an edge on a lot of his peers. Whether he's being a sweeper 'keeper and mopping up opposition counter-attacks or pinging long passes into the channels to set up breaks, he's always seeking to play on the front foot.
Statistically, Alisson outperformed some of the world's best goalkeepers last season:
Replacing Courtois would be a huge challenge for Alisson, though, as the Belgian has been a fine performer for Chelsea for many years.
Since being handed the starting spot at Stamford Bridge ahead of Petr Cech in the 2014-15 season, Courtois has been outstanding for the Blues in the main. With him in goal, Chelsea have won two Premier League titles, with Courtois offering an enormous presence between the sticks.
Per Kristof Terreur of Het Laatste Nieuws, the 26-year-old has been excellent for club and country for many years:
There are some major stylistic differences between Alisson and Courtois, so a period of transition may be in order if the Blues do end up signing the Roma man. For the defence, having the Brazilian behind them would allow them to push higher up the pitch, although they would also likely be on the ball a lot more given the way Alisson distributes.
If Courtois is to move to Madrid, it would be intriguing to see how he fared—especially given the Belgium star spent three seasons on loan at Atletico Madrid earlier in his career. The 'keeper would have to oust Keylor Navas for a starting spot too.