Alison Bender is joined by Dan Kilpatrick, Tony Evans and Mattias Karen to assess the impact of Tottenham's derby win. (2:47)

Arsenal striker Alexandre Lacazette has been ruled out for four to six weeks after undergoing a minor procedure on his knee, limiting the club's attacking options for their upcoming Europa League tie against Ostersund.

Arsenal said on Tuesday that Lacazette "had an arthroscopy on his left knee in London" and that he "will now undergo a period of rehabilitation."

The injury comes at a particularly bad time for Lacazette and the team as the France international had been expected to start in both legs of the round-of-32 tie against Ostersund.

Lacazette has lost his Premier League starting place to new signing Pierre-Emerick Aubameyang, but the former Borussia Dortmund forward is cup tied in the Europa League.

Lacazette's absence leaves Danny Welbeck as Arsene Wenger's only real option up front after the club sold Olivier Giroud to Chelsea in January. Arsenal play at the Swedish side on Thursday with the return leg at the Emirates a week later.

Wenger had backed Lacazette to return to his best form quickly after admitting in the wake of Saturday's loss to Tottenham Hotspur that the forward's confidence had been dented lately.

Lacazette came on as a substitute at Wembley Stadium but missed the team's best chance for an equaliser and has only scored one goal since Dec. 2.