Joey Barton has described Arsenal forward Alexis Sanchez as being "inconsistent", claiming that the big-money signing has failed to turn up in the big matches so far this season.

The 26-year-old has scored 13 goals for the Gunners since making a £35m move to North London from Barcelona in the summer.

Despite his impressive early strike rate, Queens Park Rangers midfielder Barton insists that Sanchez must still do more against the division's fellow big boys in order to justify his hefty price tag.

"I said he was inconsistent, from what I saw for Udinese and Barcelona," he told Forever Sports magazine. "You see him now, great at home against a smaller side but disappears against Manchester United."

Arsenal are currently sixth in the Premier League table heading into this weekend's meeting with Liverpool at Anfield.