Real Madrid forward Vinícius Júnior admits he is "angry" with himself and has vowed to return to top form.
The Brazilian forward has set up three goals but scored just once in 10 appearances this season.
"I'm not saying I'm worried, but I'm angry with myself for not being in my best version," Vinícius told reporters after Madrid's 4-3 comeback win at Roma in Wednesday's Champions League game.
"In the end, Vini always returns. I am certain.
Vinícius Júnior has vowed to rediscover his best form. Getty "It's a difficult time for me, but I have to keep working; things will turn around. I know I'm not at my best right now, but I've been through worse times before and managed to bounce back."
Vinícius, 26, in his ninth season at Madrid, agreed this summer a new deal to remain at the club until 2032.
"I arrived [at Madrid] very young, an 18-year-old, and I have always shown my face for this club, for this team," he said. "When I was 18, many people laughed at me, saying I wouldn't score any goals -- and today, I have over 100 with this jersey. Many titles, too... I don't even need to name them. Many have doubted me, yet I've always stood up for this club -- which is why I've signed on for another six years. But the good form will return, and the goals will come back; I'm certain of that -- I have no doubt at all."
It's been a difficult week for Vinícius. He was sent off in Madrid's 1-0 win over Villarreal on Saturday for pulling Nathan Saliba's hair.
Vinícius was handed a four-match ban which means he will miss the Clásico against Barcelona at the Camp Nou on Oct. 25.
Although Vinícius started on Wednesday, he was visibly annoyed when he was replaced in the 59th minute with Madrid trailing 3-1. His Brazil teammate, Endrick, came on in his place and scored Madrid's equaliser after Carlos Espí had reduced the arrears.
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"It's normal for me to get upset about being substituted because I always want to play, to be well to help the team," Vinícius said.
"Today it hasn't been possible. In the end, the substitutions helped us. They changed the match. Endrick came on and made a great impact -- he shifted the dynamic and even scored a goal. He was the best player in the second half. We hope he continues to develop so he can keep contributing, as should other players like Carlos [Espi], who often comes on for just a few minutes. They are really helping us a lot."