DAVIE, Fla. -- How hard was it for Miami Dolphins rookie running back Jay Ajayi to sit and watch his team from the sidelines the last two months?

“I would probably say it’s been some of the longest eight weeks of my life,” Ajayi said Monday.

The long wait is over for Miami’s fifth-round pick. Ajayi is officially off injured reserve and eligible to make his regular-season debut Sunday against the Buffalo Bills.

Ajayi injured his ribs in the preseason and was put on IR with the designation to return. The rookie was able to practice the last two weeks and run on the scout team. That helped him get back into football shape and get his legs under him. But potentially playing Sunday would be another step up in intensity.

“It feels good. It definitely was a different feeling waking up [Monday] morning,” Ajayi said. “It was a long time coming for sure. I’m just waiting to find out if I will get activated and I’m getting ready to play.”

The Dolphins have until Saturday to decide if Ajayi will make his debut. Miami’s running game has had its ups and downs this year, and Ajayi has the potential to add some punch and power behind starter Lamar Miller.

Ajayi's college numbers were off the charts last season: He rushed for 1,823 yards and had 32 total touchdowns at Boise State.

“I’m ready to get it going,” Ajayi said. “I feel like I’m an all-around back that can also make big plays for this team. I just want to be able to help contribute to our great offense.”