As a Brazilian I follow the Brazilian League closely and I can say the rising player here.
That's how I rate the prospects considering Gabriel Jesus as 10/10 prospect:
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São Paulo state:
Palmeiras
> Yerry Mina (22 yo), centre back 10/10, first team of Colombia squad.
> Miguel Borja (24 yo), striker 8/10, in Colombia he is ahead of Bacca and being Falcão's sub. His finish has a worldclass power.
> Tchê Tchê (24 yo), midfielder 6/10, he is a box to box but can play everywhere even as a fullback. Very talented but is too skinny and weak.
> Vitinho and Alanzinho. They are too young and I can't say precisely about them.
São Paulo
> Christian Cueva (25 yo), attacking midfielder 8/10, number 10 and the best player of Peru's NT. He tried to play in Spain once when he was younger and failed but he has improved now. His playstyle remembers Isco.
> Rodrigo Caio (23 yo), centre back or defensive midfielder 7/10, he was de CB of Olympic squad of Brazil 2016. Valencia tried to sign him but he failed the medical exams.
> João Schimidt (DM), Luiz Araújo (ST), and Lucas Fernandes (AM). I didn't say enough from them. They are young and look like good prospects.
Santos
> Zeca (22 yo), left and right back 6/10. He is right footed but is playing as left back but can also play as right back. He took Emerson Palmieri (AS Roma) place when both played in Santos.
> Thiago Maia (20 yo), central midfielder 7/10. He is being very good for Santos, good defensively and creating chances.
> Lucas Lima (26 yo) and Vitor Bueno (22yo) both attacking midfielder 6/10. I think both are a bit overhyped in Brazil, Lucas Lima is called up for the NT some times.
Corinthians
> Fagner (27 yo), right back 7/10. Tite call him up ahead of Mariano. I don't think Fagner is better than Mariano but he did the job well in the last Brazil match when Dani Alves wasn't able to play.
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Rio de Janeiro state:
Flamengo
> Felipe Vizeu (20 yo), striker 6/10. He hasn't getting playing time for Flamengo but I like him so much. I think he can do well in a middle club in Europe and improve a lot.
> Miguel Trauco (24 yo), left back 8/10. He is amazing attacking but bad defending. He was the best player in Peruvian League last year even playing as fullback. If he can't fix his defending skills along this season I would drop his rate to 7/10.
> Vinicius Jr. and Lucas Paquetá. They are too young yet to say anything serious.
Fluminense
There's a lot of young talents playing for this team. I would say the best are:
> Richarlison (19 yo), striker 7/10.
> Jefferson Orejuela (24 yo) and Junior Sornoza (23 yo). Both are midfielders from Ecuador. They are being so class for Fluminense I would say they are being 8/10.
Botafogo
I can't really say there is a good prospect playing for them. Maybe Victor Luis (23 yo) who is a left back great defensively but not that great offensively.
Vasco da Gama:
The supporters like Douglas Luiz (midfielder,18 yo) and Thalles (striker, 21 yo). But I have never seen they playing.
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Minas Gerais state:
Atlético Mineiro
> Juan Cazares (25 yo), midfielder 7/10. He is very very talented but he is a problematic guy. I don't think he will do great in Europe with his behavior.
> Rómulo Otero (midfielder, 24 yo) and Gabriel (centre back, 22 yo). I haven't seen enough from them but the Atlético's fans like them so much.
Cruzeiro
> Giorgian De Arrascaeta (22 yo), attacking midfielder 7/10. He is often called up for Uruguay National Team. He is talented and I think he will succeed in Europe someday.
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Rio Grande do Sul state:
Grêmio
> Luan (24 yo), forward 7/10. He plays more like a second striker, good pass and mobility. I think he got his peak and won't improve more. He could play in a middle club in Europe but I don't think he would fit well in a bigger club.
Internacional
> Valdívia (attacking midfielder, 22 yo), William (right back, 22 yo), and Brenner (striker, 23 yo). They are doing well for Internacional but I don't think they would do well in Europe but no one in Brazil would think that Casemiro would fit in a great European club then he turns into a monster like he is today.
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Those were the prospects of the 12 big clubs in Brazil. But the middle clubs have some good prospects as well, like Willian Pottker (striker, Ponte Preta), Juninho (centre back, Coritiba)...
Yerry Mina was a player we we're linked to not that long ago IIRC, but it seems Barca have quite a stronghold on him, first refusal/option to buy type deal I think.
Thiago Maia is a player I have heard a lot of good things about, and from what I've seen of him a 7/10 surprises me a little, considered by many to be one of the very brightest talents in Brazil.
As for South American talents outside of Brazil, There are a few possible targets.
Sebastián Driussi - 21, Forward, River Plate (Argentina)
Agüero/Suárez/Alexis style forward, lots of pace and power with a low centre of gravity. He's a sharp finisher and can play anywhere across the front line with ease. Also, despite not being the biggest he is excellent in the air and scores his fair share of headers. He also has quite a lot of experience for his age having 55 league appearances already. He has 12 goals in 19 games in all competitions so far this season.
Wikipedia link
Transfermarkt link
Video:
Ezequiel Barco - 18, Attacking Midfielder, Independiente (Argentina)
Very raw young playmaker in the Argentine top flight. Great ball control and an excellent dribbler. Seems a little light and inexperienced, and has a tendency to hold on to the ball for too long. Probably not a candidate to come straight into the City squad but could well get a loan move to one of the top flight European leagues. He's managed 12 appearances so far this season.
Wikipedia link
Transfermarkt link
Video:
Joaquín Ardaiz - 18, Striker, Danubio (Uruguay)
A tall cultured striker who has been heavily linked to Chelsea in the recent press and has been linked to Liverpool, Real Madrid, Barcelona, Porto and City in the past. He has drawn comparisons with both Luis Suárez and Zlatan Ibrahimovic and has a £25m price-tag. There are questions over his attitude after being spotted fighting outside of a youth team game with Liverpool. He has a transfer agreed to move to another Uruguayan club, Tanque Sisley, but that shouldn't stand in the way of a big-money move to Europe. So far this season he has managed 3 goals and 2 assists.
Wikipedia link
Transfermarkt link
Video:
Other players who we could take a Zuculini-esque punt on and/or farm out to our sisters in US/Aus/Uruguay:
Rodin Quiñones - 21, Right-back/Winger/Forward, Atlético Nacional (Colombia),
LINK - 5 caps for Colombia U20
Jaime Carreño - 20, Central Midfielder/Winger, Universidad Católica (Chile),
LINK - Uncapped but called up for the National side in 2015
Pablo Galdames - 20, Defensive Midfielder, Unión Española (Chile),
LINK - 2 caps for Chile
Romel Quiñónez - 24, Goalkeeper, Bolívar (Bolivia),
LINK - 14 caps for Bolivia
Saúl Salcedo - 19, Centre-back, Olimpia (Paraguay),
LINK - 5 caps for Paraguay U20