Press Association “[I’ve learned] a lot [from Arsene Wenger]. He is a coach who has many years in football and with Arsenal. I am learning from him and from my peers every day in training. I’m doing my best to be a better player every day.” While Arsenal have not been short of attacking options, with Chile forward Alexis Sanchez in fine form following a £30million summer move from Barcelona, the Gunners have been left brutally exposed at the back where their options have been hit by injuries to full-back Mathieu Debuchy and centre-half Laurent Koscielny. Debuchy suffered an ankle injury against Manchester City in September but has started to step up his recovery, while Koscielny has been sidelined by a troublesome Achilles problem with no firm return target set. “We are missing our defensive solidity at the moment, due to injuries,” said Wenger, who sanctioned the sale of captain Thomas Vermaelen to Barcelona in August. “We are paying the price for Debuchy’s (injury), because (Calum) Chambers is a central defender. “I think we have a very good balance between Koscielny and (Per) Mertesacker, so we are losing experience at the back at the moment.” German playmaker Mesut Ozil has also been out of action for several weeks after sustaining a knee injury in the defeat at Chelsea before the last international break, and is not expected to be available again until the start of 2015. Wenger, though, is confident the former Real Madrid star, Arsenal’s club-record signing, can still make a big impact this season. “He will not be back until January. He came back from the World Cup with an injury,” said Wenger. “He had a very good first season with us. I think we will see the best of Ozil in the seasons to come.” Arsenal host Manchester United on Saturday aiming to recover from the 2-1 defeat at Swansea before the international break which left them in sixth place, 12 points behind leaders Chelsea. Speaking during an hour-long television interview with beIN Sports, Wenger said: “It is not established at all that he will leave at Christmas. “It is me who sets the price and (the reported deal) doesn’t correspond at all to his price. He is not for sale and there is no offer. “Podolski plays a position where there is a big competition. He came very late from his holidays [after the World Cup in the summer], so he started after his team-mates and was not good physically.” Costa Rica forward Joel Campbell is another who has found first-team chances difficult come by with Arsenal this season. However, Campbell issued a video on his personal website dismissing reports he was seeking a move away, having just retuned to the Emirates Stadium following a productive loan spell at Olympiacos. “What they have been saying is not true, I’m very calm. I have not been furious,” the 22-year-old said on www.sports.bycampbell.com. “Obviously, yes, I would like to be playing, but that’s something that has to be earned day by day. I have to keep training and waiting for the opportunity, I know it’s a very competitive team. “Arsenal is one of the best teams in the world where there are many important players. I have to be patient, keep training and I know my chance will arrive and I’ll have to take advantage of it when it comes. Podolski has yet to start a game for the Gunners in the Barclays Premier League this season, instead used as an impact player from the bench – as he was when he netted a dramatic last-minute winner in the Champions League away to Anderlecht. Wenger, though, stressed the 29-year-old had to face up to the competition for places in the Arsenal frontline and rejected reports any cut-price deal was on the table, with the likes of Napoli said to be one of several interested clubs. Arsenal manager Arsene Wenger insists Lukas Podolski is “not for sale” – even though the German forward indicated he could look for first-team football elsewhere when the transfer window opens in January.