Handling Lionel Messi will be 'huge challenge' for Spain, admits Mikel Merino

Argentina skipper Messi, 39, has been pivotal in dragging the defending champions into Sunday's final in East Rutherford, orchestrating a 2-1 semi-final victory over England with two assists.

Messi, the tournament's joint top-scorer with eight goals, also inspired a dramatic comeback against Egypt in the last 16, when Argentina fought back from 2-0 down with 11 minutes remaining to win 3-2.

"It's a huge challenge, an incredible motivation for me and the whole team," Merino said of facing Messi.

"Being able to play against a side like Argentina, which has already won this trophy, makes the match even more significant, and I'm very happy to be experiencing this moment," Merino told reporters at Spain's training base in East Hanover, New Jersey.

Arsenal ace Merino has played a decisive role in Spain's road to the final, coming off the substitutes bench to score late winners in a last-16 defeat of Portugal and a quarter-final victory over Belgium.

"I have incredible confidence in myself and my abilities, and every time I step onto the pitch, I believe I can make an impact for the team," Merino stated.

"But honestly, it doesn't matter who the hero is; the important thing is that the team wins in the end. "When you win a title, it belongs to everyone, not just the starting XI," he added.

Merino meanwhile enthused about the "impressive" talent of 19-year-old Lamine Yamal, who will face Messi for the first time in a clash representing the past and the future of FC Barcelona.

Merino, 30, predicted that the final would be "an intense match" and that the referee would need to "control the intensity and frequency of challenges and fouls."

"The faster the ball moves between us, the less time the opposition has to commit a foul," he noted.

The midfielder, who said he did not have "very clear memories" of Spain's first World Cup title in 2010, recalled the admiration of that trailblazing side.

"Being able to represent our country today and be those same players for new generations -- for the children watching us -- is something magical," he said.