Takeover target Asciano is hopeful Canada's Brookfield Infrastructure can still pull off its $8.9 billion bid despite local logistics firm Qube moving to block the marriage.
Qube last week acquired a 19.99 per cent stake in the ports and rail operator to block what would be one of the largest corporate takeovers in Australian history.
Asciano on Tuesday said its board was considering the implications of Qube's move, but told shareholders "the board continues to unanimously recommend that you vote in favour of the Brookfield scheme, in the absence of a superior proposal".
Asciano shareholders are due to vote on the Brookfield proposal on November 10, immediately following the company's annual general meeting.
The operator of the Patrick ports business and Pacific National rail business needs the backing of 75 per cent of its shareholders to proceed with the plan.
IG market strategist Evan Lucas said despite Asciano's backing, Brookfield's bid faces uncertainty, given the issues raised by Qube's holding as well as the competition watchdog's concerns.
"On face value, Brookfield's offer is compelling value. But there are now two very big issues related to the deal," he told AAP.
Qube, which is chaired by former Patrick boss Chris Corrigan, teamed up with Canada Pension Plan Investment Board fund and investor Global Investment Partners to buy nearly $1.7 billion worth of Asciano's shares.
The consortium does not plan to vote in favour of the Brookfield offer, and has instead offered to consider several options including talking with Asciano or Brookfield for a carve-up of Asciano's assets, or seeking board representation.
Qube is mainly interested in acquiring the Patrick container terminals business in Melbourne, Sydney, Brisbane and Fremantle, as well as Asciano's stevedoring operations.
If the Qube consortium's plan is successful, GIP and CPPIB will take over Asciano's Pacific National rail, the country's largest private rail freight business.
The competition watchdog has also voiced concern over the Brookfield bid.
The Australian Competition and Consumer Commission in October said the massive takeover could lead to rail haulage in Western Australia and Queensland being dominated by the Canadian transport and utilities giant.
It said it would take another two months to assess the impact of the deal.
Asciano said the delay in the ACCC's decision would lead to a pushback in the deal timetable. Accordingly, the hearing date for the proposal's court approval has been postponed to December 21.
Asciano shares closed nine cents, or 1.1 per cent, higher at $8.19 on Tuesday.