Pierre-Emerick Aubameyang, Philippe Coutinho and Alexis Sanchez stole the headlines during the winter transfer window, but it's Michy Batshuayi who has been writing them ever since.

The 24-year-old striker has made a huge impact at Borussia Dortmund following his six-month loan move from English Premier League side Chelsea, registering five goals and one assist in just four appearances in all competitions.

If he was on the fringes of the Belgium squad a month ago, the Muscles from Brussels - sorry, Jean-Claude - is now firmly on Red Devils coach Roberto Martinez's FIFA 2018 World Cup radar.

"Michy's gone to Borussia Dortmund and as a striker you need to score that first goal as quickly as you can, he scored two in his first game," Martinez told TalkSport. "You can see that he's been liberated. He's scoring with his eyes closed. He's the best winter transfer in Europe."

There's no arguing with that. After scoring a brace and serving up a match-winning assist on his debut against Cologne, Batshuayi broke the deadlock against Hamburg and then put two past Serie A outfit Atalanta in the UEFA Europa League last 32. Not bad at all considering his bit-part role at parent club Chelsea.

Watch: Batshuayi's emphatic Dortmund debut

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"Michy was always ready at Chelsea, but the competition was really strong in that number nine role," Martinez continued. "You can see he's happy, free and sometimes a move in the winter window gives you that. It's given him a very strong opportunity to be in the World Cup squad because of the environment he's found."

Batshuayi has scored five goals in 13 senior international appearances for Belgium to date, but on current form he might not be a bad shout for top scorer at this summer's football showcase in Russia. Watch this space...

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