Atletico Madrid failed to win for a third successive game in all competitions as an inspired performance from Ruben Blanco secured Celta Vigo an unexpected 0-0 draw at the Wanda Metropolitano.
Diego Simeone's side saw their 100 per cent LaLiga record come to an emphatic end against Real Sociedad last weekend, while they rallied on Wednesday to secure a 2-2 Champions League draw with Juventus.
However, their efforts in clawing back a two-goal deficit against the Serie A champions appeared to have taken a toll judging by their performance against Celta, with a sluggish Atletico failing to score at home in league action for the first time since May 2018.
Hector Herrera was rewarded for his equaliser off the bench in midweek with a first LaLiga start, while Simeone also selected Angel Correa in an attack-minded starting XI.
Yet for all their exerted efforts going forward, Atletico were unable to find a way to beat the outstanding Blanco.
He kept the home team at bay with a trio of fine saves in the first half, starting with an acrobatic effort to turn away Felipe's header from Kieran Trippier's inswinging free-kick.
The visiting goalkeeper also tipped over a rising long-range drive from Renan Lodi, with Blanco then denying Joao Felix's on-target prod from the resulting corner.
Koke tested the 24-year-old reflexes again from distance early in a second half where Atletico became increasingly frustrated with each passing minute.
Lodi's decision to go for goal from a tight angle rather than cross for the waiting Alvaro Morata summed up a below-par performance, while they were grateful substitute Pione Sisto failed to do better with a back-post opportunity in the closing minutes of a quickly forgettable encounter.
What does it mean? Sluggish Atleti come up short
After two tough fixtures, it is perhaps understandable Atleti were a little flat, despite the best efforts of a raucous home crowd to inspire their team.
Worryingly for Simeone, they have now managed just five goals in as many LaLiga outings in 2019-20, despite having 20 attempts on Saturday.
Blanco makes a point for Celta
The away team were resilient in defence but still relied on their goalkeeper to pick up a point on their travels. Blanco made five saves in total, the best of them his early denial of Felipe's close-range header.
Joao Felix fails to fire before departure
The Portugal international has still managed just the one goal for the Spanish club since his big-money arrival from Benfica. As was also the case against La Real, the teenager was withdrawn when his side were searching for a way to find a breakthrough in attack.
With a midweek round of fixtures in Spain, Atletico Madrid travel to Real Mallorca on Wednesday. Celta, meanwhile, are in action the following day, as they host Espanyol.