The overhaul taking place at the San Francisco 49ers could have massive implications for Aussie Jarryd Hayne.

After first-year coach Jim Tomsula was sacked and replaced with Philadelphia Eagles mentor Chip Kelly, more heads on the coaching staff in San Francisco appear set to roll.

According to Eric Branch of the San Francisco Chronicle, the repercussions for the team's abysmal 2015 - they finished with a 5-11 record - haven't ended with just the head coach's removal.

The Chronicle reported only three members of last season's coaching staff will be retained in 2016: defensive co-ordinator Eric Mangini, running backs coach Tom Rathman and outside linebackers coach Jason Tarver.


Kelly will allegedly bring members of his own coaching staff with him from the Eagles, including wide receivers coach Bob Bicknell, quarterbacks coach Ryan Day and defensive line coach Jerry Azzinaro.

A notable absentee from the list of 49ers coaches to stay on next season is special teams co-ordinator Thomas McGaughey - the man responsible for honing Hayne's skills as a punt returner - the position he shone in during much of the 2015 pre-season, and occasionally in the season proper.

While far from being a raving fan of Hayne's at all times - McGaughey blamed the former NRL player for an accidental collision with a teammate in his fourth NFL game and once said he "needs to learn how to play football" with a stint on the practice squad - the Super Bowl winning staffer has previously stated he thought the 27-year-old has what it takes to make it at the highest level.

"Who knows? This year or next year he might be leading the league in punt returns," McGaughey said in October.

"He has that kind of ability.

"He's a big straight-ahead strong runner and he does a good job in making people miss in space."

In December, 49ers offensive co-ordinator Geep Chryst revealed Hayne was axed because of his three dropped returns as a punt returner, rather than his lack of knowledge at running back as some initially thought.

So, if Hayne is to transfer his phenomenal ball-running abilities over to the NFL - like he showed he could during the pre-season - then he's going to require a special teams coach with as much faith in his potential as possible.

McGaughey's likely departure means Hayne will have to prove to the new 49ers' special teams coach he is worthy of playing as a punt returner - not an easy task given he spent much of 2015 doing just that - and he runs the risk of encountering someone who isn't convinced by his ability to make a successful transition to the NFL.

However, the expected retention of Rathman as the running backs coach is a boost for the boy from Minto.

Rathman enhanced his credentials by helping new arrivals Shaun Draughn and DuJuan Harris - both new arrivals after being signed as free agents - make significant contributions just days after they began their stint with the club.

That he is reportedly one of just three existing staffers who will still coach in 2016 shows how highly he is regarded, and Hayne could only improve his play - or cement his spot in the side - as a running back under the 53-year-old's tutelage.

The ex-NSW fullback returned to the 49ers' active list after Christmas against the Detroit Lions, stepping in as a running back and receiver during their 32-17 loss.

He made a total of 47-yards for the game, rushing for 27 yards on nine carries at running back with another 20-yards from five received passes from quarterback Blaine Gabbert.

On top of his greatest ever run as a running back in the NFL, Hayne also produced a career-high three first downs as he wrote another memorable chapter in his incredible transformation.