Guerrero should have pulled one back just five minutes after the restart.
A free-kick from the left took the slightest of touches off a Leganes player and found an open Mayoral at the back post, with the striker slotting home at the back post. Leganes cut the deficit in half in the 66th minute. Amrabat was played into space on the right and he advanced to the byline before squaring to an open Brasanac, who had the simplest of tap-ins from close range.
Manchester United have been regularly linked with a move to sign the former PFA player of the year from Real Madrid since Jose Mourinho took over the reins at Old Trafford in May 2016.
Gareth Bale scored as a much-changed Real Madrid warmed up for Tuesday's Champions League semi-final second leg against Bayern Munich with a 2-1 win over Leganes on Saturday. "The attitude was exemplary".
Bale's early opener came via an initial attempt from Karim Benzema before Borja Mayoral - leading the attack in the absence of Cristiano Ronaldo - doubled the advantage in first-half stoppage time. We can't be happy with our performance in LaLiga overall. "We lost too many points in the beginning".
Speaking on the player's condition at Santiago Bernabeu, Ferdinand told BT Sport, "One thing we were all talking about here in the studio before the game finished, making those substitutions and Gareth Bale doesn't get on the pitch is a huge statement".
"There are a few games left, and I don't know what will happen".
We know what happened against Juve and past year against Bayern as well. We'll have to play like we never have before this year: we need concentration, determination, commitment, to win battles. "I'm not going to talk about motivation because having the chance to make the final of the Champions League says it all".