Atletico Madrid dealt Barcelona another harsh helping of life without Lionel Messi when Diego Simeone's well-honed team easily won 2-0 in the Spanish league on Saturday.
Luis Suarez and Thomas Lemar set up goals for each other, and only the apparent desire by Simeone to let Barcelona flounder instead of going all out on attack saved Koeman's side from a heavier loss.
Fortunately for Koeman, Barcelona's defeat came hours after club president Joan Laporta broke his silence and pledged that Koeman would stay on regardless of the result at the defending champions. His defense of Koeman came after two days of silence while Spanish media reported that Laporta was ready to fire the Dutch manager after Barcelona lost its first two Champions League games.
Koeman watched his team's latest demise from a box in the Wanda Metropolitano stands, where he served the second of a two-game ban for protesting the refereeing in a draw at Cadiz.
The first goal by Lemar caused Koeman to throw up his hands. After Suarez's second, he could only rub his eyes before he picked up his phone to presumably give more orders to assistant Alfred Schreuder in the dugout.
Schreuder made substitutes and shuffled the formation in the second half, but Diego Simeone's experienced team had no trouble locking down the three points.
There was no last push by Barcelona, no Messi-like revival to turn around a game that looked lost.
``They scored two goals with very little effort, while we could have kept on playing for three hours and not score a goal,'' Barcelona's Gerard Pique said. ``We are suffering, honestly. These are difficult times, and many of us on the team have never been through this.''
Simeone led the crowd of more than 60,000 in celebrations during the final minutes of Atletico's first match with attendance back at full capacity since the start of the pandemic. Health authorities lifted the nationwide cap of 60% attendance this week.
Atletico moved into second place, level on points with leader Real Madrid, which plays at Espanyol on Sunday.
Barcelona is in ninth place, and five points behind the top two. Koeman's side has only won three of nine matches in all competitions this season, its first without Messi in nearly two decades.
Koeman said he appreciated the backing of Laporta, even if it could have come a bit sooner.
``It is very important for me as a coach and for the squad, and it is important for the president to take this decision,`` Koeman said. ``But I know that this is Barcelona and we have to win games.''
Koeman pointed to a three-game home stretch after next week's international break as key to starting a turnaround.
With Pedri Gonzalez out with a muscle injury, Koeman aligned two other teenagers in his midfield. Midfielder Gavi Paez, who at 17 was called up for Spain's upcoming Nations League semifinal against Italy, provided some of the rare flashes Barcelona could produce in attack. Nico Gonzalez, 19, was replaced at halftime.
And just like against Bayern Munich and Benfica, which both beat Barcelona 3-0 in the Champions League, Barcelona's mix of youngsters and veterans past their prime were outclassed by Atletico.
Simeone's squad is so deep that he used former Barcelona forward Antoine Griezmann as a late substitute and let Joao Felix start alongside Suarez.
Atletico was comfortable letting Barcelona pass the ball harmlessly outside its box. It looked only a question of time before a misplaced ball would let them strike on the counter.
Felix sprung the trap in the 23rd minute after Atletico recovered the ball, threading a pass into the center that Suarez used one touch to send on for Lemar to drive over goalkeeper Marc-Andre ter Stegen.
Barcelona's long stretches of possession were only a mirage of control. Another lost ball left Barcelona completely off-balance and Pique at the mercy of Lemar and Suarez.
Suarez had all the time and space he wanted to size up Ter Stegen and put it past the 'keeper to seal the result a minute before halftime.
Suarez did not celebrate his first goal against his former team, which let him go two years ago when it needed to shed his costly contract, a story that would repeat this summer with Messi.
``From our well-ordered group, we found the space we needed and made the most of it,' Simeone said. ``This game wasn't different from our previous ones, but Messi made the difference then and he is no longer around.''
Cadiz coach Alvaro Cervera left out several players who had gone out at night without permission _ after their team had lost _ for its 0-0 draw with Valencia.
A stoppage-time goal by Manu Sanchez lifted Osasuna over Rayo Vallecano 1-0, while Mallorca edged Levante 1-0.
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