United's 1-0 win over their derby rivals ended in controversy when Anderson appeared to be booked for the second time in the match, for a challenge on David Goodwillie. However, Winter did not brandish a red card and the Saints defender remained on the pitch for the closing stages.
Houston felt it was a genuine error, saying: "If it is a mistake from Brian, then it will be an honest mistake. I did not know at the time that Anderson was due to be sent off as there was a spate of bookings and I was concentrating on which of my players had been shown a yellow card."
Houston has been delighted with the way his side responded to last week's 4-0 defeat to Rangers, with wins over Ross County in the Co-operative Insurance Cup and Saturday's victory over Saints - whice came thanks to David Goodwillie's 61st minute strike.
Houston explained: "It was a tough week with losing heavily at Rangers. After the game I asked them for two victories and we ground out a result at Ross County and won again (on Saturday). I can't ask for any more from them."
St Johnstone manager Derek McInnes believed his side should have taken something from the match.
He said: "We are disappointed by the fact that we had a lot of possession and looked the more likely team but we lost our way a bit once they got in front. The game got scrappy with all the stoppages and that suits the team that is winning.
"We looked threatening but we never put the ball in the back of the net and that is something we will need to look at. It is not often you come to places like Tannadice and look as comfortable as we did for long spells. The game was there for us but we never took our chances."
Regarding the Anderson controversy, McInnes said: "I was only made aware when the fourth official said that he thought he had been booked for the first incident.
"It wasn't clear to me that he had been booked. I would have to see it again but we can get too bogged down on analysing these positions. The bottom line was we got beaten 1-0 and never did enough to get a result."
Source: PA
Source: PA