A series of late-race caution flags on the mile oval hampered Edwards, who appeared to have a faster car at the end and remained winless in 2008 in the series formerly known as Busch.
Busch, who got his first Nationwide victory of the season last week in Texas, dominated, leading 133 of the 202 laps. But Edwards wrested the lead from Busch on lap 159 and steadily pulled away, building a lead of more than 3 seconds before debris brought out the sixth of nine cautions on lap 178.
The leaders pitted a lap later and Busch's Joe Gibbs Racing Toyota barely beat Edwards' Roush Fenway Racing Ford onto the track and held the lead, although Edwards did nose ahead momentarily on lap 197 before the final caution came out on lap 199 when Jeff Burton hit the wall.
That necessitated one more restart and Busch was able to hold off Edwards by about two car-lengths for his 13th Nationwide win and second in a row at Phoenix.
"He had a great, great car and it was just a great night for us," Busch said. "Luckily, we kept getting those cautions and we kept getting a little two-lap jump on him. He had a better car on longer runs. We got good restarts and it was good he gave me a lot of room to race him."
Busch, who moved from fifth to third in the season points, said the other key to this victory was getting out of the pits first on the last stop.
"It was much easier trying to race up front than having to pass him," Busch noted.
Edwards agreed, saying, "He got us off pit road and that hurt us a little bit.
