Manager Louis van Gaal said "facts" proved his Manchester United side were better than last year, after they were knocked out of the Champions League.
United failed to qualify for the last 16 after a 3-2 defeat at Wolfsburg.
Van Gaal said reaching the group stage, progressing further in the Capital One Cup and sitting fourth in the Premier League showed their improvement.
However, he said: "I cannot defend myself because we are out of the Champions League."
Better than last year?
United are fourth in the Premier League, having finished in the same position in Van Gaal's first season.
The former Netherlands coach, who replaced David Moyes in May 2014, led the Red Devils back into the Champions League after they failed to qualify for Europe under the Scot.
United were eliminated by Championship side Middlesbrough in the League Cup fourth round this season, following an embarrassing 4-0 second-round defeat by MK Dons in the same competition last season.
"When you see the facts - we went further in the Capital One Cup, qualified for the Champions League group, we have played all these matches and are still in a very good position in the league," he said.
"The facts say we are better than last year.
"I'm also disappointed that we are out of the Champions League."
'We didn't have an easy group'
Expectations were high among United supporters that their team would comfortably progress from a group containing German runners-up Wolfsburg, Dutch champions PSV Eindhoven and Russian runners-up CSKA Moscow.
But Van Gaal rejected suggestions his side should have qualified comfortably.
"This was a tight group so I am not agreeing with any opinion that this was an easy group," he said.
|Final Group B table|
Van Gaal perplexed by United defending
United had only conceded two goals in the previous nine matches before their trip to Wolfsburg, but were defensively uncertain throughout the Group B tie.
They conceded just three minutes after Anthony Martial's opener, then allowed Wolfsburg to score the winner within seconds of equalising for 2-2.
But Van Gaal's side did offer more attacking threat in Germany than they had in previous weeks.
United were booed off after Saturday's 0-0 draw with West Ham at Old Trafford, the fifth time in nine matches they had failed to score.
"It was a crazy match," said Van Gaal, who also saw Jesse Lingard have a goal disallowed before half-time on Tuesday.
"We didn't score many goals before and in an away match you score two goals - maybe three but one was cancelled out.
"But twice you give away a goal within two minutes of scoring, that's difficult to understand when you defend so well normally."
PSV draw cost us - Fellaini
United finished third in Group B having failed to win any of their away matches, losing at PSV Eindhoven and Wolfsburg, while drawing at CSKA Moscow.
But midfielder Marouane Fellaini believes it was United's failure to beat PSV at Old Trafford, where the sides drew 0-0, that proved costly.
"It is difficult for us. We are disappointed. We should win against PSV at home," said the 28-year-old Belgium international.
"We were not lucky against Wolfsburg. In the last 10 minutes we played with 10 men [because Chris Smalling was injured]. It was more difficult.
"But we have to forget this disappointment quickly. We have to recover quickly and focus on the next game."
Injuries pile up for United
United were without seven senior players for the trip to Wolfsburg, with skipper Wayne Rooney the most notable absentee with an ankle injury.
Argentina international Marcos Rojo dislocated his shoulder last week, while fellow defenders Luke Shaw (leg) and Antonio Valencia (foot) have long-term injuries.
England defender Phil Jones was absent with an ankle problem, while midfielders Ander Herrera and Morgan Schneiderlin are also sidelined.
Van Gaal handed a first United start to 22-year-old Uruguayan defender Guillermo Varela, and then brought on 18-year-old left-back Cameron Borthwick-Jackson when Matteo Darmian was injured during the first half.
The Dutchman's problems were compounded when stand-in skipper Smalling suffered a groin problem in the final 10 minutes.
Both Smalling and Darmian are "doubtful" for Saturday's Premier League trip to Bournemouth, Van Gaal said in his post-match news conference.