Updated

Americans Ryan Harrison and Rhyne Williams posted victories during Monday's first-round action at the BB&T Atlanta Open.

Harrison needed just over 1 hour and 43 minutes to dispatch Australian counterpart Marinko Matosevic by a 6-2, 2-6, 6-3 count, while Williams required 80 minutes to take down fellow wild-card entrant and countryman Denis Kudla, 7-5, 6-4.

The 21-year-old Harrison is still seeking his first career title, though the Louisiana native claimed the doubles crown here last year along with partner Matthew Ebden. He'll take on Igor Sijsling from the Netherlands in the next round.

Matosevic, 27, has also come up empty in the championship ledger, but was a semifinalist in Memphis earlier this year.

Williams will continue on to try and match a semifinal appearance in Houston as his best finish this year. The Knoxville, TN resident awaits the winner of Tuesday's battle between Australian Lleyton Hewitt and Edouard Roger-Vasselin of France.