Erling Haaland's competitive nature means he shows signs of frustration even in training, a mentality that has impressed Borussia Dortmund coach Lucien Favre.

Haaland has enjoyed a remarkable start to life at Dortmund following his January arrival from Salzburg in a reported €20million transfer.

The Norwegian striker has already scored eight times in just five Bundesliga matches and 11 in seven in all for his new club.

The 19-year-old stunned Paris Saint-Germain in the Champions League last 16 on Tuesday, scoring both of Dortmund's goals in their 2-1 first-leg victory at Signal Iduna Park.

That brace took him to 10 Champions League goals in fewer games than any other player in history, having incredibly netted eight times in six group-stage appearances with Salzburg before the turn of the year.

Favre is unsurprisingly delighted with the teenager's impact and shed light on his mentality, with Haaland seemingly taking training just as seriously as matches.

"It's great what he is doing," Favre told reporters on Thursday, as Dortmund prepare for Saturday's trip to Werder Bremen.

"As I have already said, he has a great mentality and always wants to look ahead. He always wants to train.

"When we play during training and he is losing or not scoring, he is not happy at all. This is very, very positive.

"We know what he is capable of, you [the media] realised this, too."

Haaland is by no means the only young player to be impressing at Dortmund currently, however. Gio Reyna - son of former Bayer Leverkusen, Rangers and Manchester City midfielder Claudio - has also caught the eye of late.

The 17-year-old has made seven appearances for the first team, scoring once, and was influential off the bench against PSG, his darting run and well-placed pass setting up Haaland's stunning winner.

For Favre, the English-born American's ability is obvious.

"We have kept out eye on Gio for a long time," Favre added. "He was with us in the US [during Dortmund's pre-season training camp] training and has been in [full first-team] training several times.

"If you don't see his quality, you're blind. He is very clever, very intelligent. Bit by bit, he has to be playing more, or he has to play from the beginning.

"Of course, at 17, he still has a lot ahead of him and can make great progress, but he already has a great mindset."