HAMSTRING tightness is delaying Brent Prismall's return to football, with the Essendon midfielder still at least a month away from being available for selection.

Prismall underwent a knee reconstruction after tearing his anterior cruciate ligament in round 19 last year and had a graft taken from his hamstring during the surgery.

His hamstring issues are similar to those lingering with fellow Bomber Jason Winderlich since his own knee reconstruction, with Prismall struggling when he steps up his workload.  

"It's not a major setback, but he is getting irritation with his hamstring and it is causing him some concerns," Essendon football manager Paul Hamilton told AFL.com.au.

"He would love to be back putting his hand up very soon, but he's been noticing it over the past six weeks."

Prismall, who turns 26 in July, is working on strengthening the muscle to avoid a strain before he jumps into full training.

He is on the club's long-term injury list and will need at least several games in the VFL before pushing for a spot in Essendon's senior side.

Experienced duo David Hille (neck) and Mark McVeigh (hip) could return through the VFL this Saturday for Bendigo Gold, and second-year midfielder Michael Ross is moving closer to playing his first game of the season.
 
Ross, who played two games last season in his debut year, hurt his ankle during a VFL practice match in March.

Hamilton said the 20-year-old had endured an unpredictable case of bone bruising that has hampered his rehabilitation.
 
"It's really a week-to-week proposition to see how he is and how he's going," Hamilton said.

"He showed a little bit [last year] so hopefully he can start to get himself up and running in the second half of the year."

Clubs are now able to promote a rookie to the senior list regardless of whether they have a player on the long-term injury list through the AFL's mid-season rookie rule.

Essendon would need to be within its total player payments to elevate another rookie - forward Cory Dell'Olio has already been elevated - but Hamilton said the Bombers wouldn't rush into making a decision.

"The only time we would bring someone up is if we are playing them that week," Hamilton said.

Mature-age rookies Mark Baguley and Brendan Lee appear to be leading the race for a senior position if the Bombers go down that path.

Callum Twomey is a reporter for the AFL website. Follow him on Twitter at @AFL_CalTwomey