Wayne Rooney handed Manchester United and England a boost when he made his comeback from a two-month injury lay-off.
The England captain emerged unscathed from a 61-minute run-out for United's Under-21 side in a 1-0 win against Middlesbrough at Old Trafford.
Rooney appeared to be moving freely as the striker stepped up his recovery from a medial knee ligament injury that has raised doubts about his prospects of starting for England at the European Championship finals in France this summer.
A few neat touches aside, it was a largely subdued performance from Rooney, who sent a free-kick high over the bar early in the second half, although he was seen remonstrating with referee Anthony Backhouse in the 33rd minute for a poor challenge by Jonny Burn on Joe Rothwell that went unpunished.
Van Gaal watched Rooney from the directors' box but Roy Hodgson was not at Old Trafford to witness the forward's first appearance since February 13.
Van Gaal must now decide whether to include Rooney - who has missed United's past 12 matches and England's friendlies against Germany and Holland - in his squad to face West Ham United in their FA Cup quarter-final replay at Upton Park.
That game has taken on even greater importance for Van Gaal's job prospects after United's implosion at White Hart Lane on Monday, when they conceded three goals in six minutes to lose 3-0. The club are now four points adrift of fourth-placed Manchester City in the race for a Champions League spot.
Rooney will have a maximum of seven matches to prove his fitness before Hodgson names his squad on May 12, provided he features against West Ham and United win that game to set up a semifinal meeting with Everton a week on Saturday.
United's final league game of the season at home to Bournemouth takes place three days after Hodgson's squad announcement.
Although Rooney's place in the England squad seems assured barring any potential injury complications, there are no guarantees he will start the opening game against Russia in Marseille on June 11.
Next month will be critical for Rooney to prove his fitness, as well as his form, as he competes with Tottenham's Harry Kane, Jamie Vardy, of Leicester City, Arsenal's Danny Welbeck, and Raheem Sterling, of Manchester City, for a starting place.
Such selection problems do not concern Van Gaal, who must hope his team improve hugely on the Spurs debacle against West Ham and cope better with Andy Carroll than Arsenal managed on Saturday.
Carroll scored a nine-minute hat-trick in a 3-3 draw and Van Gaal has warned his defenders to be on guard against the striker.
"I have seen the Andy Carroll show [against Arsenal]," the United manager said. "Carroll has special qualities. We have seen that against Arsenal and they have great central defenders but still he could do that. So we have to cope with Andy Carroll.
"Everybody knows that this is the last chance [of a trophy].
"The players of Manchester United have to cope with that pressure, they have done it always."