Ramon Nunez scored twice as Leeds came from behind to beat Doncaster in the second round of the Carling Cup.
The home side were ahead after just two minutes through James Hayter and then dominated the opening half hour.
They failed to capitalise though and were made to pay when Nunez fired in an equaliser for the visitors.
The second half was more even with both sides having chances, but it was Nunez who had the final say, firing in from 18 yards to win it for Leeds.
The Honduras international Nunez was one of six Leeds changes from the Leeds side that drew 2-2 at West Ham on Sunday, and rewarded manager Simon Grayson by taking his season tally to five goals from three starts.
Doncaster had made three changes themselves from the weekend, hoping to find some form following a run of four straight league defeats at the start of the season.
Initially it paid dividends as the home side began much brighter and seized a second-minute lead when Hayter turned in Giles Barnes' cross.
They proceeded to dominate the following 30 minutes but were unable to take advantage, with Kyle Bennett particularly wasteful by hitting the post when through one-on-one with United keeper Paul Rachubka.
Leeds punished the home side for such profligacy when Andy Keogh headed on a long-ball which Nunez allowed to bounce before looping a shot in from 20 yards.
Rovers began the second half as they had the first but there wastefulness continued with Bennett twice going close with a back-header and then a mis-directed 20-yard drive.
Nunez had no such issues at the other end though and with seven minutes remaining he positioned himself on the edge of the box and lashed home a loose ball to give Leeds the lead.
Bennett clipped the post again late on, but by then his side's resolve had been broken.