That calculation backfired spectacularly on Thursday as voters stripped her Conservative Party of a parliamentary majority and forced her to turn to a small political party from Northern Ireland to prop up a minority government.
Irish Prime Minister Enda Kenny tweeted Sunday that he had spoken with May "and indicated my concern that nothing should happen to put (the Good Friday Agreement) at risk".
Since the election, most of the members of May's cabinet have kept quiet on the issue of her future, adding to speculation that her days as prime minister are numbered. But Britain's Saturday newspapers agreed she is just clinging on.
The Labour leader, who has insisted the Conservatives lost the election despite being the largest party, was photographed by Times columnist Giles Coren at the football practice in sunny north London as the Prime Minister grappled with the fallout of losing her majority.
May had called the election to build upon her majority; instead, the party lost it.
Theresa May has struck a deal with the Democratic Unionists that will allow her to form a government.
On Friday, May announced that she would form a new government with the support of the Democratic Unionist Party, which was founded by Protestant firebrand Ian Paisley and which in the past has shared power with Sinn Fein, the political wing of the Irish Republican Party, in Northern Ireland.
If May can get through this vote with the help of the DUP she can continue in government.
"Now we're in the position we find ourselves in tonight so it will be an incredibly hard evening for her".
If neither party can command a majority in parliament for their Queen's Speech, it is likely a fresh election would be called.
"That's not a matter for me", she said.
Mrs May responded that the DUP deal "would provide stability and certainty for the United Kingdom going forward", her office said.
The British pound tumbled against the USA dollar GBP= and the euro EURGBP= after the election result.
But it will be another blow to the prime minister, who has been heavily reliant on their advice and support since her previous job as home secretary.
On Brexit, Corbyn said he wanted "tariff-free access to the European market" and to maintain membership of key European agencies, as well as European Convention on Human Rights and European Court of Human Rights but he confirmed he would press ahead with leaving the EU if he became prime minister.
"That's what people voted for last June". Most parties want to do this because it means they can successfully pass bills through parliament knowing they can rely on more than half of MPs to support their bills and vote to make them laws.
A failure to get legislation through parliament could eventually trigger another election. For the first time in nearly a century, the party lost their Canterbury seat to Labour. "May fights to remain PM", said the front page of the Daily Telegraph, while the Times of London said: "May stares into the abyss".
The debate on the Queen's Speech usually lasts about five or six days.
The Conservatives' ability to adhere to such a commitment if they are wedded to a parliamentary alliance with the DUP has been questioned. "The task of restoring orderly government in order to make sense of Brexit is now a national emergency, and it falls to them". He said a new election might be necessary later this year or early in 2018.