"Sean gives us depth at the point guard spot," Suns general manager Steve Kerr said. "We like his instincts and his ability to run a team. He also puts a lot of pressure on the ball."
Singletary was the 42nd overall pick in the 2008 draft by the Sacramento Kings, who quickly sent him along with Patrick Ewing Jr. and Ron Artest to Houston in exchange for Bobby Jackson, Donte Greene and a 2009 first-round draft pick.
The 6-foot guard was a member of the Kings' Las Vegas Summer League team, where he averaged 5.8 points, 4.8 rebounds and 4.4 assists playing in each of the club's five games.
A four-year standout at Virginia, Singletary was a three-time All-ACC selection who led his team in scoring with 19.8 points per game last season. He was the lone Division I player to rank in the top 40 in both scoring and assists.
Strawberry was the 59th overall pick by the Suns in the 2007 draft, and averaged 2.2 points in 33 games last season.