Sales of Wu Lei's replica Espanyol jersey have exceeded 10,000 in China, according to the La Liga club's official shirt maker, Kelme.

The shirt has become a hot seller because of Wu's impressive performances since joining the club last month, said Liu Zejun, chief marketing officer of Kelme China.

"His jersey went out of stock shortly after the signing was announced about a month ago, and sales have kept soaring since then," said Liu.

Wu joined Espanyol from Shanghai SIPG in a historic deal last month that made him the first Chinese to sign for a Spanish top-flight club on a permanent basis.

The 27-year-old has hit the ground running in Spain, helping Espanyol move away from the relegation zone with some key contributions in attack-although he has yet to find the net for his new side.

Barcelona-based Espanyol is also enjoying a boom in sales of other merchandise in China, with over 2,000 items of club gear such as tracksuits and hoodies sold as of Feb 24.

"Wu's move to Espanyol came as a happy surprise to the company, and we expect that he will keep in shape," said Liu.

Founded in Spain in 1963, Kelme is the official shirt supplier for a number of La Liga clubs, including Real Valladolid, Huesca, Rayo Vallecano and Alaves.

In 2014, Kelme licensed its trademark to a textile company located in Jinjiang, a sportswear manufacturing hub in Fujian province.