It has been a miserable campaign in Europe so far after losses to Bayern Munich and Galatasaray but they managed to scrape victory against Copenhagen in their last fixture.
Nevertheless, Ten Hag needs another three points to help alleviate the pressure on him and has been boosted by the return of Rashford to his squad.
After being asked about the forward's availability, Ten Hag said: "He is 100 per cent [ready to return]. Rashy missed one game with a small knock."
However, there was bad news for United fans as Ten Hag went on to confirm that key players Casemiro and Lisandro Martinez are facing lengthy spells out and would not be back until Christmas.
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"Casemiro and Martinez are really strong injuries, I don't expect them back before Christmas," the Dutchman said.
Casemiro suffered a hamstring injury against Newcastle while Martinez will undergo an operation on his foot.
Rashford missed United's victory against Fulham on Saturday, where the Red Devils claimed a 1-0 win at Craven Cottage.
The 26-year-old hasn't been in the best of form of late, however, his struggles pale into significance compared to that of teammate Antony.
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While Antony has come in for criticism this season, Rashford is still looking to kickstart his campaign after just one goal in all competitions.
The Brazilian forward has no goals or assists in 11 outings this season but Ten Hag believes Antony should be cut some slack by the critics.
On Antony's form, Ten Hag said: "He was out for a couple weeks so that broke the rhythm.
"Had a good pre-season but had a break so now has to get himself back in good form. It's hard work."
Manchester United train ahead of their Champions League clash against Copenhagen
Last season, the England international hit top form after scoring 30 goals in all competitions and assisting 10 - the best season of his career.
But so far, the United academy graduate has been miles off the pace while the Red Devils have toiled.
Ten Hag has come under pressure this season after eight defeats already, including heavy defeats to Manchester City, Newcastle and Arsenal.
Victory against Copenhagen is vital to bolster their chances of qualification to the latter rounds of the Champions League on Wednesday.
They currently sit third in the group, behind Bayern Munich and Galatasaray.
However, United looked unimpressive in the reverse fixture at Old Trafford after they scraped a 1-0 win.
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Andre Onana proved the hero after pulling off a last-gasp penalty save but Ten Hag will be hoping for a more comfortable night this time round.