UAE lead the standings following a 2-0 win over Kuwait in their opening fixture last month and travel to the Al Abbassiyin Stadium on Wednesday aware that Syria will be looking to build on their impressive goalless draw with Iran in Tehran.
Metsu has warned his team that they will need to perform at their best to claim a second straight win and retain their 100% start to the campaign.
"The game will not be easy at all and our team need to be at their best if we want to get a good result from the match," he said.
"The game is a challenge for us and we must put in all our effort to win this challenge in order to maintain our chances to win one of the places in the next round."
Metsu admitted that he was surprised by Syria's point against Iran and would be satisfied with a draw.
"We have studied the Syrian national team and we spotted their strengths and weaknesses especially in the game against Iran.
"We must prepare for a tough match on Wednesday. Syrian football has demonstrated good progress, especially with the clubs in the AFC Champions League.
"Syria's players are physically strong and they are also quick. They had a top performance in the first game against Iran and they surprised everyone with the result.
"A draw will be a good result for us because it will maintain our position at the top of the group."
UAE warmed up for the fixture with a 1-1 draw with Gulf neighbours Oman and Metsu believes the friendly was vital for his team's preparation.
"The game against Oman is totally different from the game against Syria but it was a good preparation for us and for the new players that we have called up to the national team," added the Frenchman, who led Al Ain to glory in the inaugural AFC Champions League.
UAE are without defender Haidar Alo Ali, who injured his right foot while playing for Al Wahda in an AFC Champions League match against Syrian side Al Karama earlier this month.
Al Jazira defender Saleh Obaid is also out injured while there are also concerns about the availability of defender Tareq Darwish, who missed Al Wasl's match with Saipa in the AFC Champions League last week.
Syria coach Fajr Ibrahim is seeking to build on the draw with Iran and is targeting another good result.
"We are optimistic that we can have a good result in the game," said Ibrahim.
"The players showed great enthusiasm in training and we are hoping to have another positive result like we did in the first match against Iran."
Ibrahim, who observed UAE's friendly draw with Oman, added: "We have a complete squad for the match and the players have been in great spirits.
"We respect UAE a lot but the most important thing for us is to get the three points from the game."
The hosts expect to enjoy the support of a 45,000-strong crowd after the Syria FA offered free entry to spectators.