Jackie McNamara pointed to renewed self belief among his players as the reason for Dundee United's impressive form since he took over from Peter Houston.
The former Partick Thistle boss has guided United to two home wins on the trot, their first since August.
"It would be unfair to Peter to say this and that has changed," said McNamara after
"Sometimes it's a bit of belief with the players. You can see the threat we carry. There are some good players."
And he added: "We're making the training enjoyable and we let them come here and express themselves. But there is still a lot we need to work on."
Last week United beat Rangers in the Scottish Cup, with Johnny Russell registering an early strike that day.
And in only McNamara's second game in charge of the Terrors, Russell was at it again, spinning and firing past Hearts keeper Jamie MacDonald in the second minute.
Hearts lost Marius Zaliukas to injury when he twisted his ankle badly and the visitors then had Ryan Stevenson sent off, rather controversially, for a challenge on Gary Mackay-Steven.
Willo Flood rounded off a beautiful move in 62 minutes to make it 2-0 and, although Michael Ngoo slammed in a goal for Hearts 14 minutes later, substitute Michael Gardyne made the points secure just before full-time.
"I thought we controlled it," said McNamara. "If I'm nit-picking I'm disappointed to lose a goal.
"Hearts were down to 10 men and sitting in. We seemed to make things a little difficult in terms of possession instead of going to hurt them."
United travel to Celtic Park next Saturday and the former Celtic full-back believes his new charges can give the runaway league leaders a tough match.
"If the lads have a bit of belief in themselves and pass the ball properly we can give anyone problems," he said.
"I want to win every game. That is my target. I don't set my team out to draw a game.
"The fans are paying money to watch us and hopefully we can entertain them. That's the industry we are in.
"Gary Mackay-Steven running at defenders - I think he got three of their back four booked with his running today.
"That's what people come to watch."