Arsenal and Manchester United on alert as Pierre-Emerick Aubameyang skips training

The hottest striker in European football right now has a big decision to make.

Pierre-Emerick Aubameyang enjoyed a 2015 to remember as he led the line with Borussia Dortmund. The Gabon international has played a key role in Dortmund's free-scoring ways, this season, after opting to stay with the Bundesliga side last summer. The January transfer window is now open and Dortmund have been forced to batten down the hatches again. Arsenal and Manchester United are two sides said to be most keen to secure the services of the 26-year-old. Both teams could really do with a consistent goalscorer - Aubameyang has scored 21 league goals in the first half of a prolific season.

The striker has fuelled transfer speculation, today, by his non-appearance at a Dortmund training session. A club official told reporters that Aubameyang was not present due to 'personal reasons'.

However, only last week, Dortmund chief executive Hans-Joachim Watzke told Bild, "One must never make the mistake of believing a club like [ours] is dependent on a player." Asked about his goalscoring team-mate this afternoon, Dortmund's Matthias Ginter said, "We all hope he'll stay. "He's very important, on the pitch and off, for what he contributes to the group atmosphere." Were Aubameyang to depart, it would cost his suitors somewhere in the region of €50-55m.