The on-loan Inter Milan midfielder impressed as a second-half substitute.
"Saphir came very well from the bench," Koeman said. "He gave new spirit to the team after the 1-0 and he was very good. Duan, OK sometimes he needs to play a little quicker because we don't get the time to play easy in the Premier League or against these type of opponents, you need to be a little more fast, but it was a good test, we know that and we have more prepared ourselves."
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