Rosicky (thigh) and Koscielny (calf) both sat out Saturday’s dramatic FA Cup semi-final penalty shootout win over Wigan Athletic at Wembley.
We have a battle with Everton and we must be consistent until the end of the season
Wenger also confirmed that Lukas Podolski, Alex Oxlade-Chamberlain and Nacho Monreal are all struggling with injuries ahead of the Hammers’ visit to Emirates Stadium.
“We have plenty of uncertainties,” said Wenger. “We will have lots of tests today.
“Tomas Rosicky and Laurent Koscielny will undergo tests today. Lukas Podolski, Alex Oxlade-Chamberlain and Nacho Monreal are also doubts.”
Asked about the fitness of Jack Wilshere, who has been out with a foot injury since early March, Wenger replied: “He will start to run this week, he is progressing well.”
Wenger, meanwhile, admitted that Arsenal have a fight on their hands to secure Champions League qualification after being overtaken by Everton in the race for fourth at the weekend.
“It’s important to focus on the Premier League,” he said. “We need to find our tempo for a derby game.
“We have a battle with Everton and we must be consistent until the end of the season.”
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