Brewster – who scored 11 goals in 22 games on loan at Swansea last season – was first sent back to the top corner after being found by James Milner, before continuing with an exquisite loft finish for his second after a good work of Curtis Jones.
And Wijnaldum says he’s not surprised by the striker’s qualities in front of goal.
“I’m not ‘impressed’ because I already know what kind of quality he has,” the Dutchman told the Reds official website.
“We trained together for a few years and he also showed in training that his finish is amazing so I’m not really impressed!
Wijnaldum added that the Austrian side gave the Premier League champions a tough test in the 90 minutes, which made the emergence of new options like Brewster all the more important.
“This is how it should be. Now we have the matches, we all know it’s going to be a really tough season with a lot of games so a lot of players will be playing a lot of games, ”he said.
“So if you have a lot of players who can bring quality to the pitch, that makes it even better for the team. We are really happy that the guys who came, the young players, made the difference today.
Liverpool have now left their Austrian training camp ahead of Sunday’s Community Sheild with Arsenal, and Wijnaldum says the experience has been positive despite coronavirus concerns and a rain-soaked pitch in their first game against Stuttgart.
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“I think every training camp is a good camp, I think mostly now because we only had a little over two weeks to prepare for the Community Shield,” he added.
“It’s always good to have a good preparation in the preseason because it’s basically the preseason for the start of the season.
“It went pretty well, we had to deal with some circumstances but also that we did well, so it was a good training camp. “