Simone Inzaghi insists the second leg of Inter's Champions League last-16 tie with Feyenoord "won't be simple", despite the Nerazzurri establishing a 2-0 lead on Wednesday.

Goals either side of half-time at De Kuip from Marcus Thuram and Lautaro Martinez put Inzaghi's side in control at the halfway point in the tie.

Inter could have returned to San Siro for next week's rematch with an even greater advantage, had Timon Wellenreuther not saved Piotr Zielinski's penalty later on.

The Serie A leaders have only conceded one goal in their nine Champions League matches this season, and Inzaghi was pleased by the attitude demonstrated by his players in Rotterdam.

"[Lautaro and Thuram] played a great game, then [Mehdi] Taremi and [Marko] Arnautovic also came on and did well," the Nerazzurri head coach told reporters during his post-match press conference.

"On the wings, everyone did well. [Francesco] Acerbi, [Alessandro] Bastoni, [Yann] Bisseck, also for the availability they showed. It wasn't a simple game and the second leg won't be either."

Inzaghi also hailed stand-in goalkeeper Josep Martinez, who has deputised for Yann Sommer in recent weeks, with the latter nursing a fractured thumb sustained against Juventus last month.

The Inter boss acknowledged Martinez's performances between the sticks have left him with a selection headache when Sommer returns from injury.

"Martinez showed his qualities [against Feyenoord], which no-one had any doubts about," Inzaghi added. "He was very good at staying calm and adapting well.

"Being Inter's goalkeeper is not easy, [but] we have a goalkeeper like Sommer, who has great experience and is doing well. I will evaluate [the choice] calmly, but I am satisfied with everyone."