Speaking afterwards, Mourinho seemed to warn United fans not to expect much success from 2018-19 and claimed he could not be honest in his assessment for fear of further criticism of his methods.
United have now gone four games without a win in all competitions.
The club were forced to ask Uefa if they could delay kick-off by five minutes as a effect and it set the tone for another fitful evening at Old Trafford.
After finishing second in the Premier League last season, United are now 10th in the table after seven games, already nine points off league leaders Manchester City.
Valencia failed to take advantage of Cristiano Ronaldo's early red card in losing 2-0 to Juventus on matchday one and could yet regret not cashing in with all three points against a misfiring United side.
Google's Project Stream lets gamers play straight through the Chrome browser
For controls, you have options of a keyboard and mouse or a USB (not Bluetooth) game controller. You must have or be willing to get a Google Account, a Ubisoft account, and Chrome.
"I think it's a bad situation", he said on BT Sport. I am sat here actually surprised he survived after Saturday, the performance was that bad.
After the game, United's players were criticised for a lack of effort and attitude. [We knew] if we don't perform at least at an acceptable level, we would lose and defeat would leave us in a hard situation.
Fresh from a humbling week in which they exited the EFL Cup to Derby County and lost 3-1 to West Ham in the Premier League, Jose Mourinho's side produced another lifeless display in their second continental game of the season. In the second half there was more [desire] and the team tried even more. We tried to play but in some crucial phases we didn't have the technical quality to build from the back. We thought with 3 or 4 chances we would win the game but we didn't'.
"It's not a bad result but it's not a good result".