Simone Inzaghi hailed the improvements made by Romelu Lukaku after his penalty helped them to a 3-1 win over Udinese.
Lukaku opened the scoring in the 20th minute after Denzel Dumfries was adjudged by the VAR to have been brought down by Walace.
The Belgium international saw his first effort saved by Marco Silvestri, but the goalkeeper was ruled to have strayed off his line and Lukaku made no mistake with his second attempt.
His strike ended a 189-day drought in Serie A for Lukaku, his previous goal coming way back in August against Lecce.
Sandi Lovric levelled for Udinese but a superb Henrikh Mkhitaryan volley and a late Lautaro Martinez goal gave Inter the points.
Lukaku has seen much of his season hindered by a hamstring injury, but Inzaghi is full of belief in the on-loan Chelsea striker now his fitness issues appear to be behind him.
Inzaghi told Sky Sport Italia: "Lukaku is improving day by day, game by game, training session by training session.
"We have great faith in Rom. He had a few problems last season in London, we brought him back here and then he had this serious injury that troubled him for four months.
"If he is starting games, that means he is in good shape and playing will help him strengthen that form."
Inter are 15 points behind Serie A leaders Napoli, but the win over Udinese allows them to go into Wednesday's Champions League tie with Porto on a high.
"We knew Udinese are a very physical side with good technique who cause you a lot of problems, as we already saw in the reverse fixture," he added.
"It was a good first half with the only setback being the goal we conceded, when we should've been more focused on the loose ball.
"I am glad with the result, it is an important victory that allows us to keep going."
