Feb. 19 (UPI) -- La Liga club Atletico Madrid scored a fourth-minute goal and held on to upset Premier League leaders Liverpool in the first leg of a round of 16 matchup at the 2019-20 Champions League.
Saul Niguez had the lone score in the 1-0 triumph Tuesday at Wanda Metropolitano Stadium in Madrid.
Koke sent in a corner kick from the right side to set up the score. The in-swinging pass fell into the box, where it hit the boot of Reds center midfielder Fabinho. The loose ball then rolled right in front of the goal, where Niguez was there to poke it past Liverpool keeper Alisson.
"Hard work, persistence and always believing earned us this win," Niguez told reporters. "We scored early and then we did a great job. We earned a very big win."
Atletico had several close chances in the first half, while Liverpool could not fire shots on target. Reds star Mohamed Salah had one of Liverpool's best chances in the second half, but his header sailed just to the left of the left post in the 53rd minute.
Atletico continued to search for a second goal down the stretch, before stuffing the box with defenders to limit Liverpool's chances for an equalizer.
"I am not disappointed about how we played. I've seen much worse games in my life," Liverpool manager Jurgen Klopp said. "It was absolutely OK. How I said we were not good enough in the last third, that's it. I didn't expect that we would have around about 70 percent possession.
"I actually thought we would have a little bit more of the game, but we are not surprised. 1-0 and you are not in the best moment. You try to defend it with all you have, and that's what they did."
Liverpool had 73 percent of the possession in the loss. The Reds had eight shots with none on target. Atletico had seven shots with two on target.
"We had the ball most of the game but, unfortunately, we couldn't create massive opportunities," Liverpool star Virgil van Dijk told BT Sport. "But we still have another 90 minutes to set it straight, and we should be full of confidence still."
The Reds have several Premier League games before returning for the second leg of their round of 16 matchup against Atletico. Liverpool -- the defending Champions League winners -- can still advance to the quarterfinals, but need to limit Atletico's scores on the road when they host the La Liga club in Liverpool, England. The Reds will most likely need to advance on goal differential or total goals scored. Liverpool can advance to the quarterfinals if they beat Atletico by at least two scores or score three or more times in a win March 11 at Anfield.
The first leg of the Champions League quarterfinals is April 7 and April 8.
Liverpool hosts West Ham in Premier League play at 3 p.m. EST Monday at Anfield. Atletico hosts Villarreal in La Liga at 3 p.m. EST Sunday in Madrid.