Neymar has been named in the Paris Saint-Germain squad for Tuesday's Champions League last-16 first leg at Borussia Dortmund, despite missing the French club's last four games through injury.
The world's most expensive player has been struggling with a rib problem, but was expected to be fit in time for the game at Signal Iduna Park.
The Brazilian missed last season's surprise last-16 loss to Manchester United with a foot injury, while he also sat out the second leg of the defeat at the same stage of the competition by Real Madrid in 2018.
Neymar was rested, along with Kylian Mbappe, for PSG's remarkable 4-4 draw at Amiens in Ligue 1 on Saturday.
"He will be in Dortmund, I'm sure of it, but without being in the best shape he was in two weeks ago," Tuchel said before the Amiens game.
"But he will help us. I am sure and convinced of that."
PSG are yet to reach the Champions League semi-finals since being bought by their Qatari owners in 2011, with their run to the last four in 1994-95 still the closest they have come to lifting the European Cup.
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