The Spanish publication says that the 25-year-old holding midfielder will be given the chance to impress Zinedine Zidane in pre-season but the idea is for the La Liga giants to sell him on for around €15m later in the window.
Mascarell arrived at the Real academy in 2010 and progressed through the youth ranks of the club before former manager Jose Mourinho gave him his La Liga debut during a 4-2 victory over Osasuna in June 2013.
The Canary Islander continued his development in successive loan spells at Derby County and Sporting Gijon but in the summer of 2016 Real decided to part ways with him on a permanent basis and sell him to Eintracht Frankfurt.
AS says that Los Blancos included a €4m buy-back clause in the deal and are ready to trigger it to make him their first signing of the summer transfer window.
Following an impressive debut campaign in the Bundesliga, Mascarell missed the opening half of the current season due to an achillies injury but he has returned to his best in recent games and Real believe that they could sell him for a profit in the summer.
AS says that a number of clubs from the Bundelisga and the Premier League are already monitoring the situation and Real would be ready to let him go for around €15m.
The Spanish publication did't disclose the names of the clubs interested in the holding midfielder but during the January transfer window Marca reported that both Everton and Sevilla were keen on his services.
AS says that Mascarell will be given a chance to impress Zidane – or his potential replacement - during pre-season with the likes of Casemiro, Luka Modric, Toni Kroos, Mateo Kovacic and Isco expected to arrive late following their participation in the World Cup.
Real have two players to cover the holding position in the form of Casemiro and Marcos Llorente but AS says that Eintracht plan to ask Los Blancos to loan them a replacement in order to fill the gap left by the departure of Mascarell.