Los Blancos are now without a win in their last three league matches, following a defeat at Valencia and a draw with Unai Emery’s Villarreal this month.
A poor performance from Real Madrid played its part in Alaves securing a crucial three points in the capital, but Pablo Machin’s side were good value for the win on the overall balance of play.
Lucas Perez got the ball rolling for the visitors after just four minutes, as he confidently tucked home from the penalty spot, following Nacho Fernandez’s handball.
The visitors had the better chances again before the break, as Thibaut Courtois produced a vital stop to deny Perez second goal.
However, the Belgian international was at fault when Alaves did double their advantage just after the restart, as his poor clearance was converted by Joselu.
Brazilian midfielder Casemiro bundled home a consolation for Real Madrid in the final five minutes, and Zidane’s side almost snatched a late equaliser as Isco fired an added time effort against the bar.
Image via Real Madrid CF on Twitter