A first-half Cassio strike was enough to secure Adelaide United their second win of the season as they edged Central Coast Mariners 1-0 at Hindmarsh Stadium today.

The Brazilian hit a free-kick in the 33rd minute that had goalkeeper Danny Vukovic beaten before striking the underside of the crossbar and crossing the line.

The Mariners enjoyed plenty of possession after the break but failed to really create anything in the final third as the Reds held firm for the win.

The victory was Adelaide's first since the opening game of the season and moves them up to fourth in the A-League table while the Mariners remain above them in third on goal difference.