Upon his arrival in Rochester, Gaustad registered 53 points (14 goals and 39 assists) in 80 games while also seeing his first action with the parent club, the Buffalo Sabres.

On February 7, 2007, in a game against the Ottawa Senators, Gaustad's leg was cut and his tendon was sliced in a collision with Dany Heatley, an injury which at the time was thought to have ended his season.

However, he did recover ahead of schedule and joined the Sabres in their 2007 Stanley Cup playoffs on May 4, 2007, for Game 5 against the New York Rangers at home in Buffalo.

After a productive campaign during the 2007–08 season, in which he registered a solid 36 points while mainly on the third and fourth lines, Gaustad was re-signed by the Sabres to a four-year, $9.2 million contract extension on the eve of the free agency period, which was set for July 1, 2008.

[3][4] Gaustad was born in Fargo, North Dakota and moved to Portland, Oregon at a young age, which he considers his hometown.