Late goals and the Video Assistant Referee were the order of the day as Portugal and Chile both had goals disallowed in their respective matches.
Portugal 2-2 Mexico
— ConfedCup?2017 (@ConfedCup2017) June 18, 2017
Portugal were denied victory in their Confederations Cup opener after Mexico scored a last-gasp equaliser to clinch a 2-2 draw at the Kazan Arena.
The European champions had twice gone in front, but they were pegged back on each occasion as El Tri came away with a share of the spoils.
The game got off to a quiet start, although the Mexicans enjoyed the lion's share of possession in the opening stages but couldn't make it count.
Cristiano Ronaldo sent out a warning when he cracked a shot against the crossbar in the 20th minute after his initial free-kick had struck the wall, before the first moment of controversy arrived.
The ball came out to the right and was driven back in, where Nani turned home into the bottom-left corner of the net, but the referee disallowed the goal with the aid of the Video Assistant Referee (VAR).
Ronaldo had a hand in their opener nine minutes before half-time as he raced towards goal on the left and drew two defenders before slipping the ball to an unmarked Ricardo Quaresma, who sold Guillermo Ochoa with a dummy to slot into an open net.
However, Mexico were back in the contest eight minutes later as a mistake from Raphael Guerreiro let in Carlos Vela, who sent in a cushioned cross for Javier Hernandez to head past Rui Patricio.
The second half was a low-key affair as both teams struggled in the final third. But Fernando Santos' side looked dangerous in the closing stages with the introduction of Andre Silva.
Quaresma tested Ochoa late on after being set up by Ronaldo, but there was nothing the keeper could do to prevent Cedric from finding the back of the net four minutes from time after initially denying Silva, only to see the ball loop up over his head off the boot of Carlos Salcedo.
Once again the goal was referred to the VAR, and after a lengthy deliberation it was allowed to stand.
However, Mexico hit back again as Hector Moreno steered a header in off the right post from a corner deep into stoppage time to salvage a point.
Cameroon 0 Chile 2
Chile opened their Confederations Cup campaign in convincing fashion with a 2-0 win over Cameroon at the Krestovsky Stadium.
The South American champions dominated proceedings in Moscow, but only had two late second-half goals to show for their efforts following the intervention of the VAR.
They had also been kept at bay by Cameroon keeper Fabrice Ondoa, who pulled off a string of fine saves to keep his team in the contest before being beaten twice at the death.
La Roja almost got off to a flying start when Eduardo Vargas connected with a low cross to steer his shot against the base of the right post in the second minute.
Ondoa was soon called into action as he denied Jose Fuenzalida on the half-volley, while Vincent Aboubakar threatened on the break for the Indomitable Lions with a low effort that was saved by Johnny Herrera.
The first controversial incident arrived just before half-time when Vargas latched onto a defence-splitting pass from Arturo Vidal and fired past Ondoa into the left corner of the net. However, the referee consulted the VAR and the goal was subsequently ruled out for offside.
Juan Antonio Pizzi's side continued to cause problems in the second half following the introduction of Alexis Sanchez. They should have opened the scoring in the 70th minute when a corner found its way to Mauricio Isla at the back post, but he headed wide from a few yards out.
Vidal then show Isla how its done 11 minutes later as he directed a towering header past Ondoa from Sanchez's inch-perfect cross on the left to give Chile a deserved lead.
Vargas would not be denied either as he secured victory in stoppage time after another referral to the VAR. Sanchez was played through on goal and saw his shot blocked by a defender, but the ball rebounded to Vargas, who scored at the second attempt from close range.