Jarryd Hayne

Baalke has also labelled Hayne’s NFL experiment a success, despite the former NRL star playing just eight games in a fractured season which included spending a number of months in the practice squad.

 “I don’t have a crystal ball, but what I do know is that he is very conscientious and this is very important to him,” Baalke told Fairfax Media.

“We are committed to this. I’m looking forward to getting him back here, I know the coaching staff is.”

Hayne fans might call his return to the 49ers' 53-man squad a Christmas miracle, while others upset at the injury-ravaged team's treatment of the former NRL star the past two months probably would call it karma.

The 49ers announced on Sunday they have promoted Hayne and inserted him back in their 53-man active roster, making him eligible to play the Detroit Lions on Sunday (Monday 5am AEDT).

The resurrection of Hayne's NFL career comes after the 49ers axed him on Halloween and two days later signed him to their practice squad.

After the final regular-season game, which this season is January 3, teams begin signing practice-squad players like Hayne to reserve/future contracts. These contracts lock in a player for the start of the league year in early March when teams' roster sizes go back to 90 players.

The 49ers are likely to offer Hayne, who was their most exciting prospect during the preseason, one of these contracts. Whether he signs it or not will depend on whether he feels he can get a better shot with another squad.

After already losing the services of running backs Carlos Hyde, Reggie Bush and Mike Davis, Gaskins became the next to suffer injury during San Francisco's morale-sapping 24-10 loss to the Cleveland Browns.

Gaskins will be subjected to the NFL's strict concussion checklist, the most recent edition of which was published in August 2014.

SANTA CLARA, CALIFORNIA — The 49ers keep adding running backs to their roster, and with none named Jarryd Hayne, you’re probably wondering if he’s adrift on a sailboat in San Francisco Bay’s choppy waters.

Nope, Hayne is entrenched on their practice squad, meaning they still want to develop him and he still wants a job in the NFL, albeit a less glamorous one that keeps him out of uniform on game days.

Injuries to their top three running backs — Carlos Hyde, Reggie Bush, and Mike Davis — have forced the 49ers to scramble at that position.

FRU chief executive officer Radrodro Tabualevu, while applauding former Fiji Bati fullback Hayne's selection, said it was the best news ahead of the Flying Fijians tricky opener against home team England at Twickenham.

Radrodro said the FRU was confident that Hayne's transition from professional rugby league to American Football together with all his achievements as a professional sportsman was an inspiration for the Vodafone Flying Fijians.

"His achievement thus far is remarkable and manifests a nothing is impossible attitude," he said in a media statement.

Playing primarily as a running back and punt returner, Hayne made the cut after a slew of impressive performances in the preseason that saw him finish with the second-most rushing yards of any player in the league.

The former NRL star made the first cut on Tuesday, when the squad was reduced from 85 to 75, and is now a member of one of the most storied franchises in NFL history.