The midfielder was named man-of-the-match as Thierno Barry struck the winner on the hour mark.
“It was amazing,” said Garner. “We worked so hard throughout the week. We have a very good team, a lot of brilliant players. The lads grinded it out today. We got the chance and we took it.
“We tried to nullify what they are good at which is playing through the middle. We tried to block off all the passing lanes and force it wide. Then, we waited for our moment and won it back.
"When you come to places like this, you might only get one or two chances. That is what we did and the main man put it away again!
“It was an amazing performance from the lads. We set out exactly what we wanted to do which was to come here and make it hard for them and come away with three points.”