Neither player could be separated in a closely-fought opening set until Sijsling made a crucial break in the 11th game to move 6-5 ahead. The Dutchman then held to love as he claimed the set.
Sijsling made a bright start to the second set, breaking Raonic's first service game to establish an advantage. With the score at 5-4 to Sijsling, Raonic made life difficult for his opponent, saving three set points before Sijsling finally claimed the set at the fourth attempt.
In the third set both players gave little away off their own serves and it went to a tie-break.
Sijsling booked his place in the next round by taking it 7-4.