Ryan Giggs believes Manchester United's negative approach to October's 0-0 draw at Liverpool has continued to undermine their season.
Jose Mourinho's side had won six and drawn one of seven Premier League games heading into the game against its old rival at Anfield, which proved to be a dour stalemate.
United could have snatched the points through a clear chance Romelu Lukaku missed before half-time, but the limited attacking intent shown marked a stark contrast to Pep Guardiola's swashbuckling Manchester City.
The league leader won 2-1 at Old Trafford earlier this month to go 11 points clear at the top of the table and will face Bristol City in the semifinals of the EFL Cup after the Championship side humbled United at Ashton Gate this week.
Record appearance maker Giggs conceded United's current standing is tough to take in comparison to its neighbour's healthy plight.
"In isolation, they're doing okay,” he told The Times . "But when you bring City into it, it's more difficult because City have been so good.
"If we had beaten them at Old Trafford, it would have been interesting to see how City reacted. United could have kicked on from that too. But it didn't happen."
Mourinho's pragmatism has drawn increased criticism in some quarters, although Giggs - who left his role as assistant manager at Old Trafford when the Portuguese succeeded Louis van Gaal last year - points out Alex Ferguson was not averse to taking a safety-first attitude against the best.
The former Wales winger would like to see the page of the Mourinho playbook implemented on Merseyside thrown away, even if he recognises the greater quality and flair in Manchester at present resides on the other side of town.
"You can't just go gung-ho against every team, especially when I don't think the players are outstanding like they have been in the past,” he said.
"Sometimes you have to adapt. Park Ji-sung man-marked [Andrea] Pirlo at Old Trafford. But it has been disappointing in the big games this year.
"Liverpool was the killer because they weren't in good form and United were flying. Then there was a lot of negativity and I don't think we've recovered from that game."
Giggs added: "You want entertainment. It's part of the history, part of the culture. You also want to win. As a United fan, you want both.
"That was the way I played. I wanted to entertain, beat men, excite the crowd. But do we have the players to do that?
"It's horrible to say this, but you look at City and [David] Silva, [Kevin] De Bruyne, [Leroy] Sane, [Raheem] Sterling, [Gabriel] Jesus… they're brilliant to watch.
"Not only that, but their best players work so hard when they've not got the ball as well. Do United have that quality? It's hard to say it, but probably not at the moment."