Zinedine Zidane's side will have eyes on the Champions League final in two weeks time against Liverpool, while Celta are ending their campaign with a whimper, having won just one of their last nine matches.
Gareth Bale may yet have a big role to play in the Champions League final.
Gareth Bale fired Los Blancos ahead in the 13th minute after converting a pass from Croatia midfielder, Luka Modric.
With less than nine minutes to the end of the normal regulation time, Germany global, Toni Kroos competed six goal rout to put Los Blancos three points behind city rivals, Atletico with one game to wrap this season up.
Real Madrid full-back Marcelo would love to play with Neymar at the European giants.
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Mercedes didn't pit either Hamilton or the now second-placed Bottas and both cruised to the flag on their one-stop strategy. Leclerc scored points for the second race in a row, setting him up nicely for the next in his home town of Monaco.
Leo Messi scored a wonder goal in a 2-2 draw with Real Madrid at the weekend and he is likely to prove a handful for the opposition defenders.
The visitors were quick to look for a reply minutes later, but a shot from Maxi flying wide was the closest they came to a goal.
The Celta goalkeeper kept out a header before the hour to deny Bale his hat-trick and the officials erred in disallowing Benzema's follow-up for offside.
Isco, also hoping to earn a place for the Liverpool game, curled home a fantastic strike, Achraf Hakimi scored and Sergi Gomez slid in an own goal.
Alvarez emerged from a chastening outing with credit and denied Asensio's fellow replacement Borja Mayoral at close quarters before Kroos coolly found the corner.