Croft and Heaslip featured in all three internationals in the Republic, with O'Driscoll starting the first two before injury prevented him from playing a part in the historic third Test success in Johannesburg.
Both Heaslip and O'Driscoll have been in stunning form for Leinster throughout the calendar year as the Dubliners finished third in the Magners League and became Heineken Cup Champions for the first time in their history.
The No8 and inside centre had previously excelled in Ireland's first Grand Slam triumph since 1948 and have since cemented their status as world leaders in Lions colours.
Leicester flanker Croft became a household name in 2009, scoring a brace of tries for the Lions in the first Test against South Africa in at Durban's ABSA Stadium.
Having missed out on selection for Ian McGeechan's original 37-man squad at the end of April, the now 24-year-old firmly established himself as one of the world's most-exciting back row players with a series of fine performances on tour.
Croft, Heaslip and O'Driscoll have been nominated for the high-profile accolade alongside Australian playmaker Matt Giteau, All Black skipper Richie McCaw and Springbok internationals Francois Steyn and Fourie du Preez, both of whom played against the Lions this summer.
Fellow 2009 Lion Shane Williams is the current holder of the award, with Croft, Heaslip and O'Driscoll hoping to become the fourth Lion to be named the world's best player after Keith Wood and Jonny Wilkinson picked up the trophy in 2001 and 2003 respectively.
The nominations were made by a panel of famous rugby names, with former Lions Will Greenwood, Gavin Hastings, Scott Quinnell and Paul Wallace joining Raphaël Ibanez, Francois Pienaar, Agustin Pichot, Tana Umaga, and John Eales in watching over 60 hours of action from 46 matches, awarding points to the three players they thought stood out in each match.
"The IRB Player of the Year Award is the ultimate accolade for a player and takes into account performances in all internationals played during the year, including the RBS Six Nations, British & Irish Lions Test Series, Tri Nations and the June and November Tests," said IRB Chairman Bernard Lapasset.
"The list of past winners includes the iconic names of the decade - Jonny Wilkinson, Schalk Burger, Richie McCaw, Fabien Galthié, Dan Carter, Bryan Habana and Keith Wood have all been worthy recipients of the Award.
"Now that the shortlist has been selected the panel will reconvene at the completion of the November tests when the IRB Player of the Year will be selected. The announcement will be made at the conclusion of the final weekend of matches."
IRB World Player of the Year previous winners
2001 - Keith Wood
2002 - Fabien Galthié
2003 - Jonny Wilkinson
2004 - Schalk Burger
2005 - Dan Carter
2006 - Richie McCaw
2007 - Bryan Habanna
2008 - Shane Williams
Bold denotes Lions tourist