Despite an upturn in form of late, Reading are still among the favourites to be relegated to the npower Championship after just one season in the top flight.
Leigertwood remains hopeful the Royals will stay up, but he admits a cup run could prove key to that happening.
The Reading midfielder fondly remembers his cup run with the then-Championship side two years ago, when the Royals beat Everton and West Brom before exiting the competition with a 1-0 quarter-final defeat to eventual winners Manchester City.
Reading's cup run that year coincided with a nine-match winning streak that eventually took them to the npower Championship play-off final, and Leigertwood hopes the Royals can enjoy a similar bounce this season as they look to preserve their top flight status.
"The FA Cup run that year was good for us. It definitely helped our league form at the time and hopefully we can put a good run together this season," Leigertwood told a press conference.
"We beat some good teams - Everton, West Brom and we had a tough game at Stevenage.
"We went out against Manchester City and we gave a good account of ourselves there. It definitely helped our league form."
Recent history suggests Reading are primed for a decent FA Cup run.
As well as their exploits in the 2010-11 season, they also reached the quarter-finals the previous campaign, achieving a historic win at Liverpool on the way.
Such famous victories have been hard to come by this term as Reading have struggled to adapt to life back in the top flight, where they sit just inside the bottom three, one point from safety.
But Leigertwood revealed yesterday that one of the ways the squad boost their morale is by watching clips of their exploits in the cup that year, when they also beat West Brom.
"I wasn't at the club (for the 2009-10 run), but all the lads talk about it," Leigertwood said.
"Sometimes we watch videos and look back at the clips (of the win at Anfield). We have a look at inspirational videos just to look back at the good things and just to give us a bit of inspiration."
On paper Reading should have no trouble swatting aside Leigertwood's former employers Sheffield United in the fourth round on Saturday.
The 30-year-old enjoyed a memorable season at Bramall Lane, playing his part in shock wins against Arsenal and Newcastle as United enjoyed a rollercoaster season in the top flight which eventually saw them cruelly relegated on goal difference.
The Blades have plummeted since. They were relegated to League One two years ago and now sit eight points off leaders Tranmere having been pipped to automatic promotion by bitter rivals Sheffield Wednesday last season.
Leigertwood regards the South Yorkshire club, who have won the FA Cup four times, as something of a sleeping giant.
"They are a big club, definitely," Leigertwood said.
"They are very passionate up there about their football. You are either a red or a blue.
"They were good times for me at United. I met a lot of good people up there. Unfortunately I had two injuries which kept me out for a couple of months at a time, which was quite disappointing, but when I played I was doing quite well.
"It will be a tough game on Saturday. They haven't been doing as well in their league of late but all form goes out of the window in FA Cup games so it should be an exciting game."