AIYEGBENI Yakubu last night delivered a chilling warning to Premiership defences as he prepares to start his new life at Middlesbrough - "I want to be the best striker in the world".

The Nigeria international will jet out to the Algarve with the rest of his Boro team-mates later today after finally receiving a work permit to complete his £7.5m move from Portsmouth

Only Arsenal's Thierry Henry can better Yakubu's record of 29 Premiership goals in the last two seasons, with the African terrorising defenders despite Pompey's relative lack of attacking ambition.

The likes of Stewart Downing and the fit-again Gaizka Mendieta should ensure the chances keep on coming next term and, after signing a five-year deal at the Riverside, Yakubu is hoping to establish himself amongst the world's biggest striking stars.

"I want to be the best striker in the world," said the 22-year-old, who has scored five goals in his last three games against the Teessiders.

"I've played in Israel for almost three-and-a-half-years and then with Portsmouth for two-and-a-half-years and I've scored goals wherever I've been. This is a big step forward for me and I think it will help me do even more.

"I want to score more than 20 goals. I want to close the gap on Thierry Henry and, with these players around me, I think I can do that.

"If you have good experienced players around you, you can become the best in the world.

"We have good players here who can pass the ball to me and set me up to score. When you've got players like Mendieta, Downing and (Gareth) Southgate, you're always going to have a good chance of bettering yourself."

Yakubu's arrival completes a three-year pursuit for Boro boss Steve McClaren. The England number two was first alerted to the striker's potential when the then Derby boss, Billy McEwan, recommended him after a one-week trial at Pride Park.

Work permit problems meant Yakubu was forced to ply his trade for Israeli side Maccabi Haifa at the time and, when he was eventually able to move to England, Portsmouth leapt to the front of the queue for his signature.

McClaren made an unsuccessful attempt to take him to Teesside last summer and, after finally getting his man, is confident he will only improve in the future.

"There's more to come," claimed the Boro boss, who also confirmed he had verbally agreed a new contract at the Riverside that he is expected to sign later this week.

"He can get better and improve. He has done every year so far and, with the facilities and staff we've got here at Middlesbrough, I think his best years are still to come.

"He's got proven ability. We've bought someone who's already got two years experience in the Premier League and proved he can do it.

"He's proved over the two and a half years that he's a goalscorer. He scores one goal every two games and that's a phenomenal record.

"He wants to be the best striker in the world and that's a great ambition to have. I also happen to believe that it's one he can fulfill."

With Yakubu safely on board, McClaren is certainly not short of striking talent ahead of the start of the new campaign.

Jimmy-Floyd Hasselbaink, Mark Viduka, Malcolm Christie and Danny Graham will all be at the Riverside at the start of next season, but the Boro boss is open to offers for Szilard Nemeth, Joseph-Desire Job and Massimo Maccarone.

The former is being linked with a move to Premiership new-boys Wigan, while the latter is expected to join Italian side Siena, who he spent time with last season, before the end of the month.

"We know how many we need to make sure we can go a full season," explained McClaren. "We don't want to be caught short again.

"You need quality in depth and we didn't have that last season. We got injuries to two or three of our strikers and, towards the end of the season, our goalscoring reduced rapidly.

"We need a depth of strikers because we're going to have a lot of games this season and we want to do well. But there may be an opportunity for Maccarone to go back to Siena and we are discussing that at the moment."

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