Big serving Aussie Sam Groth has been knocked out in straight sets in the first round of the Brisbane International.

Groth went down 7-6(8), 6-4 to South Korean teenager Hyeon Chung at Pat Rafter Arena on Monday night.

Groth came firing out of the blocks, racing to a 5-2 lead in the first set, before Chung rallied and found a way to combat the big hitting Groth, before eventually taking out the opening set in a tiebreak.

Groth the found himself down 4-1 in the second set, before staging a comeback of his own, however, it was not enough, with Chung holding on to take the second set 6-4.

Chung, ranked 51 in the world, will now fave Marin Cilic in the second round.

Fellow Australians Ben Mitchell and John-Patrick Smith also lost in the first round on Monday.