An entertaining contest at the Kazan Arena was first ignited when Cristiano Ronaldo fired a shot onto Mexico’s crossbar in the early stages of the match.

Having bounced back into the box, the ball was eventually diverted home by central defender Pepe, who is also Ronaldo’s team-mate at UEFA Champions League winners Real Madrid.

The goal was eventually ruled out, after the referee consulted with the Video Assistant Referees, who deemed Pepe to have been offside.

Portugal’s frustration would not last for long, as Ronaldo cleverly found Ricardo Quaresma free in the box, with the 33-year-old dancing around Mexico’s goalkeeper Guillermo Ochoa before finding the net.

Their advantage would last just eight minutes, as Mexico’s record goalscorer Javier Hernandez met a right wing cross with a diving header to pull his team level on the verge of half-time.

Portugal thought they had snatched victory in the closing stages of the match, as Cedric Soares’ deflected effort found the corner of Mexico’s net with four minutes of normal time remaining.

The European champions were to be denied victory in added time, as Hector Moreno headed in from a corner, with the aid of the post.

The result leaves hosts Russia top of Group A, following their 2-0 victory over New Zealand yesterday.

Group B would begin with the same scoreline, as Copa America winners Chile saw off the challenge of African champions Cameroon at the Otkritie Arena in Moscow.

The Video Assistant Referees would again be utilised as Chile’s Eduardo Vargas was adjudged to have been narrowly offside before he found the back of the Cameroon net in the first half.

Chile passed up the chance to take the lead when Mauricio Isla could only steer an Arturo Vidal cross wide from close range.

Vidal would succeed where his team-mate failed nine minutes from time, heading powerfully into the Cameroon net.

Chile’s victory was sealed when Vargas scored from close range in added time, after substitute Alexis Sanchez saw a shot blocked on the line.

Video replays were again consulted, but no change was made to the initial decision to award the goal.

Australia and World Cup winners Germany will meet tomorrow in their first Group B match.

The tournament is traditionally used as a warm-up for the following year's World Cup and features the home nation, the winners of six continental tournaments and the reigning FIFA World Cup holders.