The Liverpool captain made his first start of the season after recovering from a groin injury – and the 31-year-old scored the opener as he squeezed his free-kick between Ryan Giggs and Danny Welbeck in the United wall and into the net.
United substitute Javier HernÃ¡ndez rescued a point for Sir Alex Ferguson’s side with nine minutes remaining as he headed past Liverpool goalkeeper Pepe Reina.
But Gerrard believes the Reds could have won the game if they had taken their chances in the second half.
“I thought the first half was very flat,” Gerrard said. “I think both sides were anxious and a bit nervous, and maybe had too much respect for each other.
“In the second half, based on chances created, we are disappointed we didn’t take maximum points. That is credit to us and goes to show how far we’ve come.
“Without a doubt there are positives to be taken. We’re happy with the performance. We could have easily nicked the game 2-1 or even 3-1.
“We had chances with Luis [SuÃ¡rez] and Dirk [Kuyt], and the keeper pulled off a world-class save from Jordan [Henderson]. We did very well and did enough to win the game.”
Gerrard was delighted to complete the full 90 minutes but insists he is under no illusions that more work has to be done before he can produce his best form again.
“I’m stiff and tired – but that’s to be expected,” he added. “The physios and medical staff knew that [would happen].
“That’s what I’ve got to do to push on and gain maximum fitness. I still need two or three 90s under my belt to get back to 100 per cent, but I am very pleased at how my groin held up and how my body felt for the first 90. Really pleased.”
“It was a great feeling [to score]. The last six months have been really frustrating. To watch the lads from the stands is not what I like doing – I like to be out there where I can have an impact on games.
“To be out there against United experiencing the emotions against Manchester United – the biggest game against our big rivals – was very enjoyable for me.”
Meanwhile, Liverpool striker SuÃ¡rez has “categorically denied” racially abusing Patrice Evra during Saturday’s clash at Anfield.
The Football Association confirmed on Saturday that they were investigating the alleged incident after the Manchester United defender accused the Uruguayan of saying “a certain word to me at least 10 times”.
Evra said: “I was very upset. In 2011 you can’t say things like this. He knows what he said, the ref knows it, it will come out. I won’t repeat what he said, but it was a racist word, and he said it more than 10 times. He tried to wind me up. I won’t make a huge deal out of it, but it’s very upsetting and disappointing.”
A Liverpool spokesman said: “The first we knew about these allegations was 20 minutes after the final whistle when the manager was asked to go into the referee’s office and told about them.
“The first thing we did, as you would expect, is ask the player and he has categorically denied using any language of that nature.”
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