Lionel Messi squandered a second-half penalty as Argentina were held to a draw by a FIFA World Cup™ debutant on an action-packed Day 3 of the tournament.
Elsewhere, Croatia got off to a flyer in Group D while there was some good news for Egypt.
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It’s all here in our daily wrap looking at the results and news from the FIFA World Cup™ with our Russia Watch.
ARGENTINA HELD BY ICELAND
Goalkeeper Hannes Thor Halldorsson was the hero for Iceland as his second-half penalty save from Lionel Messi secured his side a sensational 1-1 draw against Argentina.
In an eventful Group D opener at the Otkrytie Arena in Moscow, Halldorsson came up big for his side as he dived to his right to frustrate Messi from the spot.
"The penalty was painful, I feel responsible,” Messi said after the match.
"We do not have to go crazy, we deserved to win, but we have to improve a lot, now we have to be calm.
"This is just beginning and we knew it would not be easy. It's a bad fight because we deserved to win, we were superior to Iceland. We have things to improve, we're going to beat Croatia."
Both goals came in a four minute period midway through the first half.
Sergio Aguero had fired the beaten finalists from four years ago ahead in the 19th minute, finally breaking his FIFA World Cup™ duck at the ninth attempt with a rising left-footed drive.
But Iceland refused to buckle, with Alfred Finnbogason capitalising on Willy Caballero's weak punch to score his country's maiden goal in the history of the tournament.
CROATIA MAKES WINNING START
Croatia moved into pole position in Group D with a hard-fought 2-0 win against Nigeria in Kaliningrad.
In a contest light on genuine goal-scoring chances, the Europeans scored in each half to take top spot in the group.
The opener came courtesy of own goal from midfielder Oghenekaro Etebo, turning a Luca Modric corner into his own net after both Ivan Perisic and Mario Mandzukic flicked the delivery on.
After the break, William Troost-Ekong man-handled Mandzukic in the box, with captain Modric coolly converting the 71st-minute penalty to give Croatia a winning start.
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They next face Argentina on Thursday, knowing a win will book their spot in the last 16.
"They [Argentina] have huge amounts of quality, but this win will boost our confidence and we will up our game," Modric said.
"We'll play a good game against Argentina. I hope we will take some points but it's going to be tough.
"They have to play for a win because of today's score, which was unexpected for them, but it's an important game for us and we will try to play our best."
GOOD NEWS FOR THE PHARAOHS
Mohamed Salah has been declared fit to face Russia in Egypt's second game at the World Cup match by the Egyptian Football Association (EFA), who confirmed he could have featured in the 1-0 defeat to Uruguay but was not risked.
Salah was an unused substitute as Egypt were undone by a Jose Gimenez header in the 89th minute in Ekaterinburg on Friday.
Liverpool forward Salah recovered from the shoulder injury he sustained in the Champions League final defeat to Real Madrid just in time to play at the World Cup, and the EFA indicated he is ready to take on the tournament hosts in their next match.
"He was fit to play against Uruguay but the coach did not want to take the risk," said the EFA.
Egypt will face a Russia side who won their opening match against Saudi Arabia 5-0, and the Pharaohs need a positive result to keep them in contention for the knock-out stage of the tournament.