Highlights: Denmark off to a winning start over Peru
Denmark started their World Cup campaign with a 1-0 victory over Peru in Saransk thanks to Yurary Poulsen's second-half strike.
Peru were beaten 1-0 by Denmark in their first World Cup finals match since 1982, with Yussuf Poulsen's strike settling the contest after the South Americans missed a first-half penalty.
Christian Cueva blew the opportunity to give the Peruvians the lead just before the interval as he blazed over a spot-kick awarded via the video assistant referee system.
Poulsen, who had given the penalty away with a foul on Cueva, then broke the deadlock in the 59th minute with a cool finish having been teed up by Christian Eriksen.
Peru's all-time top scorer Paolo Guerrero, cleared to play at the tournament in May when a Swiss court granted a temporary lifting of his 14-month drug ban, went close to equalising after coming off the bench as his backheeled effort went wide, before Jefferson Farfan was denied by the foot of Kasper Schmiechel.
While they ended up defeated, with Denmark joining France on three points in Group C, this was certainly a creditable performance from Peru as they made their long-awaited comeback at this level.
Roared on by their multitude of supporters in Saransk's Mordovia stadium, who joined them in a passionate pre-match rendition of the national anthem, they made a bright start to the match, with Yoshimar Yotun and Edison Flores shooting off-target.
The lively Andre Carrillo brought a decent save out of Schmeichel, before Farfan saw his shot diverted wide by a fine block from Danish skipper Simon Kjaer.
Denmark, for whom Thomas Delaney had shot over, were forced into a change in the 35th minute as the injured William Kvist was substituted for Lasse Schone and three minutes later Eriksen sent a free-kick into the wall, with Schone's effort on the rebound being dealt with by goalkeeper Pedro Gallese.
The VAR system then came to the fore as Peru were handed the chance to delight their fans.
Cueva went down in the box as he was challenged by Poulsen and Gambian referee Bakary Gassama went to watch the replay back on the pitchside monitor before pointing to the spot.
But Cueva, having stuttered in his run-up, horribly miscued his attempt from 12 yards and saw the ball sail over.
Cueva's misery increased just prior to the hour mark when Denmark broke forward and Poulsen latched on to Eriksen's pass and put his side in front.
Flores had a shot well saved by Schmiechel moments later before coming off for Guerrero, who almost immediately sent a header into the Leicester keeper's arms.
Peru remained on the front foot and after Guerrero's clever backheel trickled wide, Schmeichel did well once again as he kept out Farfan's shot with his boot.
Eriksen then had a chance at the other end which Gallese palmed away, and subsequent pressure from Peru proved in vain.