An expressive Diego Maradona was treated by paramedics after Argentina's dramatic 2-1 win over Nigeria on Tuesday, but he insists he is fine now.

Argentina not only required a win in their final Group D game, but needed Iceland to draw or lose against the already-qualified Croatia if they had to progress to the round of 16, following a poor start to the World Cup.

Lionel Messi finally arrived in Russia as he scored his side's opening goal in the first half with a sublimely taken touch and finish for his first goal of the tournament.

Nigeria would equalize in the second half through a Victor Moses penalty which was given away by Javier Mascherano, as the pressure was back on the South Americans as a draw would have seen the African nation go through to the last 16 instead.

However, a pinpoint cross from Gabriel Mercado was met with a first-time right-footed volley from defender Marcos Rojo to give Argentina the lead in the 86th minute as they eventually won the game in dramatic fashion with Iceland losing to Croatia 2-1.

Maradona's antics were on full display throughout the day.

Diego Maradona
Diego Maradona's antics during Argentina's win almost stole the show. In this picture, Maradona celebrates Argentina's victory following the 2018 FIFA World Cup Russia group D match between Nigeria and Argentina at Saint Petersburg Stadium in Saint Petersburg, Russia, June 26, 2018. Alex Morton/Getty Images

Before kickoff, he was seen dancing with a female Nigeria fan. The Argentina legend then celebrated euphorically when Messi scored before later being seen sleeping.

When Rojo scored the winner toward the end of the game, Maradona was ecstatic with his celebrations, even going on to make an obscene double-middle finger gesture to fans.

Videos posted online then showed the 57-year-old struggling to return to his luxury box with photos later showing paramedics treating him.

Argentine newspaper La Nacion via ESPN reported that he was being checked for low blood pressure, but he was able to walk on his own soon after.

South American television network TeleSUR's Patricia Villegas‏ later posted pictures of Maradona before and during his flight to Moscow with him appearing to be in good condition.

Maradona took to Facebook on Tuesday night, clarifying that he was not hospitalized and that he was suffering from neck pain at half-time.

"I want to tell everyone that I am fine, that I am not, nor was I, hospitalized," he wrote on Facebook, as quoted on FourFourTwo. "At half-time of the game against Nigeria, my neck hurt a lot and I suffered a decompensation."

"I was checked by a doctor and he recommended that I leave before the second half, but I wanted to stay because we were playing for everything. How could I leave? I send a kiss to everyone. Thanks for the support," he said.

Argentina's win over Nigeria sees them finish the group in second with four points as they will now face tough opposition in France in the round of 16. France finished top of their group with seven points after a bore 0-0 draw with Denmark earlier in the day.

The game will take place Saturday at the Kazan Arena in Kazan, Russia.