As one former promising youngster heads to the exit door, Arsenal are closing in on another starlet that promises to be a future star.

The Gunners confirmed that the club had agreed a fee with Real Sociedad for the sale of Carlos Vela, while, according to Sky Sports, Arsenal have come to terms with a fee for 17-year-old M'baye Niang.

Vela spent the entire last season on loan at Sociedad, scoring 11 goals. The Mexican international expressed his desire to make his move permanent and has now moved one step closer to completing the deal.

"Arsenal Football Club has announced that striker Carlos Vela is in San Sebastian this evening for final discussions about a permanent move to Spanish La Liga side Real Sociedad," the club said in a statement on their website.

"The 23-year old Mexican international spent the whole of 2011/12 on loan with the Spanish club and enjoyed a successful campaign in La Liga, scoring 12 times in 35 appearances.

"Vela made his Arsenal debut in 2008 and has made 62 appearances, scoring 11 goals."

Vela, who has spent more time on loan than actually at Arsenal in his seven-year spell, is now expected to put his final touches to a four-year deal, after Sociedad said the forward had "come home."

Niang underwent a trial with Arsenal last week and after being impressed by what he saw, Arsene Wenger has quickly gone about sealing a deal for the highly-rated teenager.

Wenger is a huge admirer of Niang, considered to be one of the brightest up-and-coming talents in the French league, and will be keen to add the 17-year-old to his side.

However, Manchester City are also reportedly interested in signing the Caen striker, and with the English Premier League champions not worried about matching the fee agreed by Arsenal, it looks it will be up to Niang to choose which club to join.

While Arsenal are unlikely to match the wages offered by City, Niang is more likely to get first-team opportunities at the North London club than at the Etihad.