Tampines hand Global first defeat in 2016
The visitors were on a 15-game winning streak since their season started but goals from Billy Mehmet, Fazrul Nawaz and Hafiz Sujad ensured the hosts walked away with a win.
Tampines took only 13 minutes to open the scoring, as Mehmet finished off a cross from Hafiz after the latter was released by Jermaine Pennant.
The lead could have been extended 10 minutes later, albeit an own goal, but Jufri Taha's cross was sliced just over by Global defender Charles Petty.
Global goalkeeper Patrick Deyto then kept out a shot from Hafiz, as the Stags attacked relentlessly in search for a second goal.
The first half looked as though it would end in Tampines' favour, but Misagh Bahadoran managed to beat Joey Sim in the 43rd minute after latching onto Matthew Hartmann's pass in the box.
There was still time for Webb to produce a moment of brilliance by beating two markers before cutting into the box but his drive was parried away by Deyto before the half-time whistle came.
Tampines finally regained the lead just after the hour mark, as Fazrul slammed in an emphatic finish .
The hosts had another chance to extend their lead two minutes later, but Deyto produced an acrobatic save to tip away Shakir Hamzah's header.
However, Tampines secured their two-goal when Irwan Shah combined well with Webb to pull the ball back towards Hafiz and the winger delivered a powerful finish into the net in the 68th minute.
Despite having a healthy lead, Tampines coach Akbar Nawas cautioned his side against complacency for the return leg on Saturday.
"I would say we are in a good state, but as you know there is another 90 minutes of football and we are only up by two goals and anything can happen," Akbar said.
"We could still lose the game... this Global team is a good team, they gave us a fight. We'll have another 90 minutes, another tough battle on Saturday."
Global coach Leigh Manson was disappointed by the result, but he believes his side fully deserved the loss.
But Manson believes his side can still overturn the deficit in the second leg.
"This was a poor performance by ourselves, that's the first time this team has lost in 2016 so we will see now their reaction," Manson said.
"The tie is not dead, if we can score the first goal in the next game, then the tie becomes alive... but we will need to have a better performance than tonight's."