Barcelona lost 2-1 at home to unheralded Russian side Rubin Kazan and Liverpool lost by the same score to visiting Lyon as the big teams struggled in the Champions League on Tuesday.
Rubin Kazan had taken just one point from the first two matches of its debut appearance in the group stage but twice led at Camp Nou to overturn a team containing Lionel Messi, Zlatan Ibrahimovic and Andres Iniesta.
Barcelona should still advance to the next round but Liverpool may be in trouble after Cesar Fabian Delgado scored in injury time to hand the five-time European champions a fourth straight loss for the first time in 22 years.
Liverpool is third in its group, six points behind leading Lyon.
Inter Milan trailed twice at home but the Italian champions salvaged a 2-2 draw with Dynamo Kiev through equalizers by Dejan Stankovic and Walter Samuel.
But Inter is now last in Group F after stretching its winless streak in Europe to six matches.
Elsewhere on a day of 31 goals and no home wins, Fiorentina won 4-3 at Debreceni and Arsenal drew 1-1 at AZ Alkmaar.
But the biggest shock was Rubin Kazan’s victory.
Aleksandr Ryazantsev put the Russian champions ahead after just 75 seconds by running onto a loose ball and smashing a shot beyond goalkeeper Victor Valdes.
Iniesta and Messi each had an appeal for a penalty turned down before Zlatan Ibrahimovic equalized for the Spanish champions three minutes after halftime.
But Alejandro Dominguez put Gokdeniz Karadeniz through into the area 25 minutes later he and Valdes with an angled shot that silenced the home crowd.
Zlatan Ibrahimovic came close to a second equaliser when he hit the crossbar with 11 minutes left and midfielder Yaya Toure hit the post with a header in the fourth minute of injury time.
“We just lacked some luck,” Ibrahimovic said.
Rubin, Barcelona and Dynamo Kiev all have four points from three games in Group F. Inter has three points.
Liverpool’s troubled season continued when it was beaten by Lyon and lost captain Steven Gerrard to a groin injury that could keep him out of Sunday’s Premier League match against fierce rival Manchester United.
The loss heaps more pressure on manager Rafa Benitez, whose team is eighth in the Premier League with four losses from nine games.
“It’s a massive disappointment; a bad result which leaves us a lot to do,” Liverpool defender Jamie Carragher said. “We’re going through a tough patch but we’ve been through them before.
“We had a lot of young lads out there tonight, if we could have hung on, it would have been a good result.”
Yossi Benayoun had put the five-time champions ahead four minutes before halftime but an injury-hit and directionless home side conceded to Maxime Gonalons midway through the second half and was then hit by a counterattack in injury time.
Sidney Govou sent a pass right across the goalmouth and, with the home defense hesitating, Cesar Fabian Delgado arrived at the far post to score the winner.
“It leaves us with a lot to do,” Liverpool defender Jamie Carragher said. “We’re going through a tough match but we’ve been through them before.
“We’ll pull through. We always do.”
Liverpool has three points from three Group E matches, six fewer than Lyon and three fewer than Fiorentina, which recovered from conceding a second-minute goal to win 4-3 at Debreceni.
Sevilla went five points clear at the top of Group G with a straightforward 3-1 win at Stuttgart, which only scored in the 74th at 3-0 down.
The Spanish team has a maximum nine points. Next is Unirea Urziceni, which benefited from two own goals to win 4-1 at Rangers.
Rangers had led through a second-minute own goal by Ricardo Vilana, but the Romanian team fought back with Marius Bilasco and Pablo Brandan scoring either side of own goals by Kyle Lafferty and Lee McCulloch.
The win moved Unirea three points ahead of the Scottish champions in its first Champions League season.
Arsenal’s lead in Group H was trimmed to a single point after Mendes da Silva scored in the third minute of injury time to earn AZ a draw.
Cesc Fabregas had put the Gunners ahead in the 36th from a pass by Robin van Persie but Mendes da Silva volleyed from close range to earn his team a second point of the season. Olympiakos beat Standard Liege 2-1 in the other game to move up to six points.