Striker Younes Khalef scored the equaliser to earn Iraq a 1-1 draw with Group A hosts Thailand in the opening match of the Asian Cup on Saturday.

Khalef headed the ball into the back of the net to secure the draw and spoil Thailand's planned celebrations on a wet and miserable night in Bangkok.

"There was a lot of rain... a lot of water in the stadium," Iraq's Portuguese coach Jorvan Vieira told reporters. "My team is a good tactical team but we cannot play in those conditions."

Khalef's goal combined with Thailand's fickle weather to ruin the hosts' hopes of a better start.

The expansive Rajamangala stadium was less than half full after the city was drenched by a tropical storm that caused flash flooding in the surrounding suburbs and kept thousands of potential spectators away.

The pitch had been badly soaked, preventing both teams from developing any fluency and they resorted to long-range shots on goal to try and break the deadlock in the second half.

"It was difficult, the state of the pitch made it hard to control the ball and we lost it in midfield a lot," Charnwit Polcheewin said. 

Iraq had the better of the first half but went behind early to a hotly disputed penalty converted by Sutee Suksomkit.

MORE SLIPPERY

Thailand's chief playmaker Datsakorn Thonglao caught the Iraq defence napping in the sixth minute when he flicked the ball to his teammate Kiatisuk Senamuang who fell in the penalty box after making light contact with Ali Rehema.

Referee Kwon Jong-chul waved away the Iraqi protests before Sutee stepped up to the spot and coolly slotted home.

Iraq were unlucky not to draw level when midfielder Salih Al Sadwn executed a brilliant bicycle kick that Kosin Hathairattanakool tipped onto the bar.

Kosin pulled off another diving save from Sadwn but was powerless to stop the Iraqis from equalising in the 31st minute when Khalef climbed above two defenders to connect with a Sadwn free-kick and head the ball into the back of the net.

Neither side could break through in the second half as the conditions began to make the pitch even more slippery as they settled for a point each.

"We did not want to play a long-ball game, but football is like this sometimes," Vieira said of Iraq's tactics and the rain.

Australia and Oman, who are also in Group A, play their opening match at the same ground on Sunday.

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