Arsenal pulled off a great escape to beat Olympiakos 3-0 in Greece on Wednesday and extend their record of consecutive qualifications to the last 16 of the Champions League to 16 seasons. And the night provided further good news for manager Arsene Wenger, with his injury-ravaged squad avoiding further casualties ahead of Sunday’s Premier League trip to Aston Villa.

Arsenal currently have seven players unavailable, many of them sidelined for the long term, which made Wednesday’s achievement all the more impressive. But the challenge does not end there. Wenger has confirmed that even the most short-term injuries -- to Alexis Sánchez, who has a hamstring strain, and captain Mikel Arteta, who has a calf problem -- will not have healed for Sunday. The duo could, though, be back to aid Arsenal over the busy Christmas period.

“Nobody will be available for Sunday,” he said in his pre-match press conference on Friday. “No Arteta and no Sánchez -- who are the shortest ones. All the others will be [available] after Christmas.”

Among those longer-term casualties is Jack Wilshere. The midfielder suffered a left-leg hairline fracture just before the start of the season in the latest in a long line of frustrating injuries for the 23-year-old. Initially expected to be out for a matter of days, Wenger has now confirmed that Wilshere will not be available again until into the new year.

“If you ask me will he will be fit before the end of December, no chance,” he said.

Another Arsenal midfielder no stranger to injuries in recent years is Tomas Rosicky. The 35-year-old was forced to undergo knee surgery after suffering an injury while on international duty with the Czech Republic this past summer. Again the initial prognosis for his recovery proved to be overly optimistic, although there is now a return date on the horizon.

“He is quite positive,” Wenger added. “He is running outside but not ready yet. End of January.”

Also still in the treatment room are Francis Coquelin and Santi Cazorla. Both have knee injuries, with Coquelin expected back at the end of February and Cazorla ruled out until March at the earliest. Danny Welbeck, who has not played since April, is not anticipated to be back available for at least another month.

Wenger could yet decide to cover for his depleted squad in the January transfer window. But Arsenal still have a challenging schedule to get through before then. Arsenal face five Premier League matches in the next three weeks. They currently sit second in the Premier League table, two points behind leaders Leicester City.