Elisabeth Terland has now scored four goals in her last three games against Leicester
Manager Marc Skinner said Manchester United were "much more like ourselves" in beating Leicester for their first Women's Super League win in four matches.
Elisabeth Terland and Celin Bizet were on target as unbeaten United ended their winless run following three successive draws.
Norway striker Terland scored deep into first-half added time, before compatriot Bizet capitalised on a CJ Bott mistake nine minutes from time to slot home her first United goal after joining from Tottenham in the summer.
"We were much more like ourselves today, much more aggressive with and without the ball," said Skinner.
"We discussed as a collective, we needed to be much more like us. I'm happy with the performance, and another clean sheet, I thought we were excellent."
United initially struggled to break down a disciplined home side that had conceded just six goals in their first seven WSL games.
They were without the injured Ella Toone, who missed the match following 96 successive league starts for United.
But it was Geyse, her replacement in the starting XI, who provided the spark the side needed in the final seconds before half-time.
Lively down the right all afternoon, the Brazilian winger looped a perfect cross on to the head of Terland to steer back across keeper Janina Leitzig and into the far corner for her fourth goal in three games against Leicester.
And the success was sealed when defender Bott miscontrolled the ball, allowing Bizet to nip in and slot under the Leicester keeper.
United's win moved them six points behind WSL leaders Chelsea, who they visit next Sunday.
Leicester meanwhile failed to net again, and are the WSL's lowest scorers with just two goals in eight games. Amandine Miquel's side are now only outside the relegation place on goal difference.
'It's a massive game against Chelsea'
United's visit to Chelsea next Sunday - rearranged following a clash with the Blues' Champions League fixtures - is now a meeting of the WSL's only two unbeaten sides.
Reigning champions Chelsea, though, have won all seven of their league matches and overcame previous leaders Manchester City on Saturday.
United, meanwhile, came into this weekend on the back of three straight draws including a dire 0-0 against Aston Villa last week where they only had five shots, one on target, in 103 minutes.
At the King Power Stadium, they were much more vibrant in attack with 23 shots and six on target.
Skinner said he and the players had specifically addressed their lack of efforts on goal against Villa before this match.
"We are an attacking team, maybe we were too passive in the last two games, but we were back at it today," he added. "We have to get back to who we are.
"We have Everton first [in the League Cup on Wednesday], then it's a massive game against Chelsea, a team that are currently top – but we are the other team who are unbeaten."
Despite not losing a league game this term and an FA Cup triumph last season, Skinner is not a universally popular figure among supporters.
He was booed by the noisy 'Skinner Out' brigade at Leigh Sports Village last week, and needed a positive result in Leicester to calm the waters.
"The reality is we've just got really passionate fans who want to win football games," said Skinner. "Once we sparked them, their engine was fantastic today.
"The energy from them was really good throughout the game. We have to entertain them. They pay their hard-earned money."
Cain howler highlights goal-shy Leicester's problems
Celin Bizet scored her first Manchester United goal after joining from Tottenham in the summer
United also needed a helping hand from Leicester forward Hannah Cain, who was guilty of one of the worst misses of the season in the 38th minute.
Having led an attack, she laid off the ball to Nicole Momiki who wriggled free in the box. United's defence recovered well, but the ball went straight back to Cain who fired wide when free and only a couple of yards out.
Most Leicester fans celebrated, thinking the ball was in the back of the net for only their third league strike of the campaign. Instead, they watched their team fall behind less than 10 minutes later.
"That's mentally hard, as you are 30 seconds from going into break at 0-0," said Miquel. "But the players made the effort in the second half to push forward as best they could. Overall the performance is not ideal, but not bad."
Goals remain hard to come by for her side, and that is the primary reason why Leicester stay stuck in the mire of the WSL's bottom half.
Since the beginning of last season, Leicester have failed to score in 14 WSL games, with 13 of those blanks in 2024 alone.
And after Aston Villa and Everton both earned their first league wins of the season on Sunday, Leicester have fallen to 10th and are level with bottom side Crystal Palace on five points.
"I don't focus on the table, it's important not to be pessimistic," added Miquel. "We try to see the good side of things, see how well they have done and try to correct mistakes.
"There is quality in this squad, it might just take a bit more time than we thought to get higher in the table. Any points can get you back up quite fast."
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