"fight desperately" is correct and usable in written English.
Example sentence: He knew the odds were against him, so he chose to fight desperately for his freedom.
Kneale slips between journey - where Wilson battles with the eugenicist Dr Potter - and destination, where Tasmanians fight desperately against the "ghost" men.
That would mean a government formulary would be hugely influential, leading drug companies to fight desperately -- and discount their products steeply -- to be on it.
This uncompromising adaptation of Elmer Rice's 1923 play, about an all-American loser turned killer named Mr. Zero, seems to take place at the bottom of a dank, dark well, where mole-like little men and women fight desperately for air.
The rueful truth is that out here the people who love environmental bond acts are very often the same people who want to pull up the ladder, who fight desperately against the new apartments and town houses needed by young couples and the working class.
Eragon and Arya fight desperately to slay Varaug.
Our minds and our bodies fight desperately to push the boredom away, sometimes restlessly, other times angrily, and sometimes with an apathy that makes life seem barely worth living.
The winged cross tattoo on the back of his neck fought desperately for attention with his classic winged tipped shirt.
The anti-Soviet forces, or Whites, headed mainly by former tsarist generals and admirals, fought desperately to overthrow the Red regime.
My mother fought desperately hard to hold her family together, reaching deep into a formative black cultural experience that relied heavily on faith and self-help.
It was a bid James Murdoch fought desperately to keep on track, sacrificing the News of the World and its journalists when the hacking storm lifted off.
On that score Asher corrects some misconceptions: Gordon was not cut down on the palace steps in an almost Christ-like scene of martyrdom, but fought desperately to the bitter end.
