Paddy Ashdown has jumped to Nick Clegg's defence after a bruising week for the deputy prime minister.
The former Liberal Democrat leader urged his party to ignore "short-term personal manoeuvring" after Matthew Oakeshott, a close ally of business secretary Vince Cable, , suggested the party needed to look at its "management" after having "lost half our market share".
Writing in the Guardian newspaper, Ashdown said he had failed where Clegg had succeeded in taking the party into government.
"In my view he has led our party in government, not flawlessly of course, but with a skill no one else in British politics could have matched and a grace under fire that should make us proud," he wrote.
"If you want to see how successful he has been, just listen to the complaints from the Tory right."
Some recent polls have pushed the Lib Dems back to single figures, leading YouGov to suggest the party could be left with only a handful of seats after the 2015 general election.
But Ashdown pointed out he was predicted to lose his Yeovil seat two years before the 1997 general election, and suggested the silly season was traditionally a time for "pre-conference bombardments on the political parties and their leaders".
Oakeshott had called for the party to "fight very hard" in government for its policies to be implemented in government, as well as getting the message across.
"We will be judged at the next election by one fact and one fact only. Whether we have had the mettle to stay the course in delivering effective government for our country at a time of crisis," Ashdown responded.
"That is the only thing that matters. All the rest is the froth."
Ashdown was one of the most sceptical Liberal Democrats during the formation phase of the coalition. But he appears to have rallied behind his leader on the basis that any other option will be worse for the junior coalition party.
He conceded that "history has not dealt the Liberal Democrats the easiest of hands", faced with "not (to say the least) natural bedfellows" and the "difficult circumstances" of austerity and a double-dip recession. Rather than panicking, Ashdown urged stability as the best option.
"These things make life more difficult," he continued. "But they do not lessen the need to see it through – or the consequences for us if we fail to do so."
Earlier this summer Cable said he was prepared to lead the party after Clegg steps down. Pundits have suggested the Lib Dems might increase their chances of saving seats at the next election if they replace Clegg as leader before the May 2015 vote.
"In tough times there are always petty ambitions to be aired, the kind suggestions of our enemies to be ignored, and helpful comments from the sidelines to be endured. But there are mighty things to be done in the next year," he wrote.
"None of this will be achieved by being distracted by mid-term summer polls, passing newspaper comments, or short-term personal manoeuvring.
"The right thing for Liberal Democrats to do now is to continue to do what we have done so well so far. Concentrate on the job we set our hands to under Clegg's leadership. Nothing else."