Speaking ahead of a visit to the North East Fife constituency, the First Minister said that only SNP MPs would be able to keep the Tories in check at Westminster.
But Labour said the comments were proof that the SNP was “hitting the panic button” and said only it could beat the Nationalists in several marginal seats.
The SNP leader said: “The choice in this election in Scotland is now crystal clear.
“It is a choice between the SNP, who will always stand up for Scotland and who will be a strong voice defending our communities, and the Tories, who want to impose deeper cuts, to pursue a damaging extreme Brexit and to silence Scotland’s voice.
“A vote for Labour at this election in Scotland simply risks letting Tory MPs in by the backdoor – helping Theresa May in her arrogant bid to crush all opposition to her right-wing agenda.
“Now that our manifesto has been launched, people can see the detailed plans the SNP have to support vital public services, including the NHS, and to stand against Tory austerity and renewed cuts.
“And with every day that passes we see more of the damage the Tories will do through their reckless approach to Brexit.”
Scottish Labour campaign manager James Kelly said: “Nicola Sturgeon has hit the panic button. Her campaign is in total disarray and has descended into utter chaos.
“Her manifesto has been torn to shreds by experts and with her personal popularity ratings in freefall, it’s clear the tide is turning against Nicola Sturgeon.
“As the Tories’ campaign also flounders, only Labour can defeat the SNP in seats across Scotland – including Edinburgh South, East Lothian, Lanark and Hamilton East, Coatbridge, Chryston and Bellshill, and Kirkcaldy and Cowdenbeath.
“A vote for Labour on June 8 will send Nicola Sturgeon a message to drop her plans for a divisive second independence referendum and get back to the job of fixing the mess she has made of our schools and hospitals.”