Trossard, 25, netted the winner against Norwich last Saturday and followed that with a fine display and an excellent first half goal against Liverpool on Wednesday.
The Belgian has returned from the lockdown fitter and stronger and has been a key reason why Albion have moved away from the relegation zone.
Against United he played as a second striker alongside Neal Maupay and took his tally to five goals for his first season in the Premier League to go with his four assists. It was a well-taken first-time volley from Tariq Lamptey's cross.
In the reverse fixture at Manchester City last August, Trossard caused a few problems for Guardiola's defence but just couldn't take his chances when the opportunities arose.
This time however, Albion head coach Graham Potter believes Trossard is in a good moment said last summer's £18m signing from Genk has improved as the season has progressed.
"I think he is (improving). He's landed from a different country into a new team, into a new environment, so it's normal that he adapts. It's a process," said Potter.
"He's got a stronger understanding of us, we understand him a bit more, there's more to come from him.
"But it's nice that he's affecting the goal, it's nice that he's contributing to the team in terms of assists and goals."
Despite Wednesday's 3-1 loss against the champions, Brighton remain a healthy eight points above the drop with four matches remaining. After the City match, Brighton travel to Southampton, before a home match against Newcastle and finish the campaign at Burnley.
“I think we need to take the positives," said Trossard. "We’ve got another really tough game again against a world class team in Manchester City on Saturday. We need to keep going until the end of the season.
“We don’t look at the table, we just try to take it game-by-game to get as many points as possible,” added the Belgian.
Apart from long-term injury victim Jose Izquierdo, who is recovering from knee surgery, Albion have a fit squad to select from.
Potter said, "We haven’t had any injuries reported from the Liverpool game, so I think we’ll be okay.
"It’s a busy period so we have to prepare as well as we can and do our best to manage the group."
Sergio Aguero, who scored twice against Albion last August, will miss Saturday’s game.
The City striker suffered a problem with his meniscus in the second game after the restart and will miss the remainder of the Premier League and FA Cup campaign after undergoing surgery in Spain last month.
City recovered in style from their 1-0 to Southampton as they hammered Newcastle 5-0 last Wednesday. Potter is fully aware his men are in for another tough evening.
“Man City, if you look at their performances, they are still at a really high level in terms of shots, in terms of chances conceded, but the points tally is key and that’s the margins of the Premier League that go against you.
"They lost 1-0 to Southampton, but on another day they win that game quite a few times. That’s the beauty of football.
“The way Man City are, they put their disappointments to bed pretty quickly, they bounced back with a really good victory against Newcastle. They’ll be ready, with their top team and we’re expecting a very tough game.
“It’s a challenge taking them on of course, but it’s the Premier League – you get stages of the season where you face the likes of Liverpool and Manchester City back-to-back like this.
"We just have to recover and prepare as well as we can, use the squad and do the best with the resources we have.”
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