Sammy Ameobi, who plays for Newcastle alongside older brother Shola, was called a "n****r" by a follower with the username @JonnnnyPhipps after the footballer tweeted a photo of a black pair of boots.
The 19-year-old, who broke into the first team at the end of last season and is becoming a fans' favourite, retweeted the abuse he received, and his attacker's account was closed down.
Both Newcastle United and the player reported the matter to police.
A Northumbria Police spokesman said on Thursday: "On Wednesday November 2 Northumbria Police arrested two young men, both aged 17, on suspicion of malicious communication.
"The arrests come after reports of a racist tweet being sent to one of the region's professional sportsmen."
Ameobi had posted a message alongside the photo of the Nike boots, saying: "There will always be a place in my heart for the all blacks."
The abuser replied: "Your hand is nearly the same colour. #n****r."
Retweeting the message, Ameobi added: "Sad to see some people are still racist nowadays."
The police investigation follows allegations of racial abuse directed at Anton Ferdinand of QPR and the Manchester United defender Patrice Evra.
Newcastle manager Alan Pardew said: "We represent the local community here and when something like this happens we have to react strongly.
"We will not tolerate any type of behaviour like that.
"With the austerity measures and everybody feeling a bit tight, everybody is feeling a bit narrow-minded and racism is coming to the fore, so maybe it is not a bad thing.
"We have been leading the world, the football world, in terms of dealing with it and maybe we should not become complacent in keeping a lid on it."