Three-times European champions Germany shrugged off their opening game loss and announced their arrival as serious contenders at Euro 2020 with an emphatic 4-2 win over highly-rated Portugal in their Group F match on Saturday.

The Germans had been beaten by world champions France in their opener prompting serious questions over their ability to make a challenge in this tournament but Joachim Loew's side responded to the pressure with an outstanding performance.

Cristiano Ronaldo had given the defending champions a 15th minute lead with his 107th international strike but Germany went in at the break 2-1 up thanks to own goals from Ruben Dias and Raphael Guerreiro.

The Germans turned on the style in the second half with efforts from Kai Havertz and the impressive Robin Gosens making it 4-1 before Diogo Jota pulled a goal back for Portugal.

The result throws the 'Group of Death' wide-open and gives Germany a strong chance of progressing to the last 16.

Germany, who face Hungary in their final game in Munich, move into second place in the group on three points, a point behind leaders France and level on points with the Portuguese. Hungary drew 1-1 with France earlier on Saturday.

It was not merely the result that suggested some pundits were wrong to write off Germany - the fluency of their passing, the killer crosses and the intelligent running was a reminder of the enduring qualities of German football that has delivered so much success on the biggest stages.

"Overall it was an outstanding performance from the team, great attitude, great spirit, we had many chances, outstanding," said Loew.

Strong start

Germany started with purpose and confidence and thought they had grabbed the lead in the fifth minute through Gosens but VAR ruled that Serge Gnabry had been in an offside position.

Against the run of play, Portugal grabbed the early lead, hitting the Germans on the break with Bernardo Silva picking out Jota on the left of the box and his low cross was tapped in from close range by Ronaldo.

It was the Portugal skipper's third goal in two games and his first ever against Germany but Joachim Loew's side kept their cool and continued to play positive football before eventually getting their reward.

The Germans drew level in the 35th minute when Joshua Kimmich's cross from the right was volleyed at the back post by Gosens and flew into the net off the outstretched foot of Portugal defender Dias as he looked to stop Havertz converting.

It was another own goal that gave Germany the lead -- Kimmich drove in a low ball from the right and Guerreiro's attempted clearance flew past his goalkeeper Rui Patricio.

Portugal replaced Bernardo Silva with Renato Sanches at the break but Germany took a firm grip on the game with a third goal six minutes after the restart -- a well-worked passing move ending with Havertz turning in a low ball from the left delivered by the influential Gosens.

Germany buzzing

Germany were buzzing now and it was no surprise when they made it 4-1 on the hour with Gosens finishing off another well constructed attack, heading home a Kimmich cross at the far post.

Portugal struck back quickly though when a deep free-kick from Guerreiro looked to be heading out but Ronaldo acrobatically hooked the ball inside to Jota who slotted home.

Sanches fired a warning of a potential comeback when he thundered a long distance drive against the woodwork but Germany's victory was never really in doubt.

The threat from the wide areas was particularly impressive with Gosens dynamic on the left and Kimmich impressive on the right while Havertz's ability to ghost into space was never neutralised by the Portugal defence.

"We wanted better movement up front. From the start there was tempo, good combinations, from the wings with Kimmich and Gosens... that was our plan and it worked," said Loew.

Despite a 3-0 win over Hungary in their opening game, Portugal's progress to the last 16 is not secure and they need to take something from their final game against France in Budapest.

"Anyone can progress. This group was always very strong," said Portugal coach Fernando Santos. "Whether we progress or not is still up to us. And we must respond to this."