United's problems were there for all to see as Juan Mata's opening goal on 17 minutes proved a unique scoring opportunity while their lack of a commanding centre half was exploited by an unmarked Jack Rodwell for Sunderland's equaliser.
They now find themselves five points adrift of early Premier League pace-setters Tottenham Hotspur, who were Sunday's big winners with a 4-0 victory over Queens Park Rangers that ensured Harry Redknapp suffered a second straight defeat and a miserable return to his former club.
In Sunday's other game, Hull City played most of the match with 10 men and came within six minutes of holding on for victory over Stoke City, but were forced to settle for a 1-1 draw.
With the transfer window edging towards a close, United were handed another reminder that nothing but significant investment in a squad that lacks depth and strength will spark an improvement in their fortunes after last season's woes.
They lacked penetration in attack with little pace or incision and while Mata tapped home following a driving run and fizzing cross from Antonio Valencia, the Spaniard was largely ineffective as a central playmaker.
As English media reported United were nearing a deal for Real Madrid's Argentina winger Angel Di Maria, many United fans were perhaps wondering if the more pressing concern lies at the back despite defender Marcos Rojo's arrival midweek.
It was Robin van Persie who let Rodwell run and jump unchecked to head Sunderland's leveller on 30 minutes, but in centre backs Phil Jones, Chris Smalling and youngster Tyler Blackett, United seemed to lack the presence of a leader.
For new manager Van Gaal, who has already claimed it will take a miracle to propel United to the Premier League summit, Sunday's woes stemmed from midfield.
"We have one point and that is not good enough for Manchester United," the Dutchman told the BBC.
"We have to work a lot. The players are very disappointed after the game because we thought we would win.
"The purpose of the game is to create more chances and score goals. We haven't created more chances. You have to recognise the fight of the opponent.
"We have reached Wayne Rooney and Robin van Persie a lot of times, but after that you need the support of the midfielders, and the combination was not good enough."
Goals were not in short supply at White Hart Lane where players condemned as costly mistakes last season starred in a 4-0 victory.
Nacer Chadli, among the expensive patchwork of players recruited when Gareth Bale left for Real Madrid, scored Tottenham's first and third while record signing Erik Lamela was pivotal in a playmaker role.
Eric Dier profited from a Lamela corner to net Tottenham's second, scoring for the second time in two weeks, and Emmanuel Adebayor rounded off the scoring with a crisp low finish.
For Redknapp, sacked by Spurs in 2012 after leading them to fourth in the Premier League, an experiment with three central defenders backfired spectacularly with Tottenham scoring three times inside the opening 37 minutes.
"We didn't play well. We got what we deserved, which is nothing. We didn't play with enough energy and I thought we were in awe of Tottenham a little bit," Redknapp said.
Hull had James Chester sent off after 14 minutes against Stoke for a lunging last-man tackle, but opened the scoring before halftime when Nikica Jelavic finished from close range after a Tom Huddlestone shot was only parried by Asmir Begovic.
The Tigers' hopes of winning back-to-back league games for the first time in 11 months were shredded when Ryan Shawcross scrambled the ball over the line after a Phil Bardsley effort hit the post.
The equaliser left Hull boss Steve Bruce fuming that a throw-in was given against his side earlier in the move.
"It baffles me. It is an awful one," he said.
"The throw-in was ours and blatantly ours. It is not as though it is a faint touch, their boy does not even want to turn round for a throw. You would think they get that right because it has cost us."