But the normally dependable defender took a huge swipe at the ball which sliced horribly beyond startled goalkeeper Steve Simonsen.
Much of the early pressure had been applied by the hosts, with captain Clive Clarke going close with a 25-yard free-kick which went marginally wide of goalkeeper Neil Sullivan.Bates, relaxing in France, was no doubt delighted with his team's third successive away win.
And manager Kevin Blackwell said he was confident he would keep his job and his team would continue to improve.
He said: "I spoke to Mr Bates briefly on the phone this morning and we will sit down for dinner sometime this week. He is a man of substance who knows about the game and his arrival has already had a positive effect.
"We have no fears about going into administration and having a ten-point deduction and no-one has to worry about getting our wages paid."
Leeds went close in the 18th minute when a David Healy effort was deflected narrowly wide by Brian Deane.Stoke managed to push Leeds back for much of the first half but created just one clear chance in the 20th minute.
Ade Akinbiyi sprinted clear from Darel Russell's lofted pass and struck a low shot which was brilliantly blocked by Sullivan.
Leeds threatened again on the half-hour, but neither Healy nor Deane could connect with Aaron Lennon's cross from the right.Leeds did pose more of an attacking threat in the 2nd half and substitute Julian Joachim, on for Lennon at half-time, forced Simonsen to make a smart save before Thomas' howler in the 72nd minute.
Stoke manager Tony Pulis made a substitution of his own as Chris Greenacre replaced Gifton Noel-Williams.
Then, in the 58th minute, Stoke's Russell clashed with Danny Pugh. Referee Iain Williamson cautioned both players.
Joachim then produced an effort from 18-yards which Simonsen saved, but the referee had more words with Russell soon afterwards, following a late challenge on Pugh.
Kevin Blackwell replaced Deane for Michael Ricketts, whose first effort was to fire a long-range free-kick low into the Stoke box.
Pugh then fired over after being set up by Joachim and although Carl Asaba as well as John Eustace replaced Clint Hill and Dave Brammer, there was no way back into the game for Stoke.Stoke will now hope Rob Hulse, who is expected to complete a £1m move from West Brom next week, can improve a dismal run of results.
This was a sixth successive defeat for Tony Pulis' men who have not scored a league goal for 545 minutes.