Friday 13 February 2015 15:10, UK
Arsenal manager Arsene Wenger admits he is mystified by Aaron Ramsey's ongoing injury problems.
The midfielder's career has been punctuated by injuries but Wenger claims the club's medical team are unable to get to the root cause of the problem.
The Wales international was a substitute for Tuesday's Premier League victory over Leicester, but was replaced after only nine minutes due to a hamstring problem.
"We haven't found the underlying reason," said Wenger, speaking ahead of the holders' FA Cup clash with Middlesbrough on Sunday.
"There is an underlying reason that is medical or bio-mechanical, because he's a guy who is serious and works hard. There is no obvious reason why he should have muscular injuries."
There's no obvious reason why he should have muscular injuries
Wenger played down the severity of the problem which is expected to keep Ramsey out for a fortnight and insisted Arsenal's training methods are sound.
"It's not a major injury. It's a grade one," he added. "We have individualised training. I don't think that is any special case that has been neglected."
Alexis Sanchez may join Ramsey on the sidelines on Sunday after receiving a blow to his knee against Leicester while midfielder Jack Wilshere is back in training following ankle surgery but will not be risked against Middlesbrough.
"Alexis Sanchez is still not able to go out (to training). He could be short," Wenger added. "Jack Wilshere is back in normal training but he has been out for four months and misses competition.
"He worked very hard, focused, committed, but it will take him a while to get back to a competitive level.
"He's motivated and focused to come back as quickly as possible.
"He worked very hard. But he has still been out for four months. What he needs now is to get back. Competition gives you that sharpness training cannot give you, because it's about a combination of fitness and speed of decision making
and it takes a while to get that back."
Midfielder Alex Oxlade-Chamberlain (groin), Mikel Arterta (ankle) and Mathieu Debuchy (shoulder) all remain missing.
"The closest of the three is Chamberlain," said Wenger, who is also without Abou Diaby (calf). He might be two weeks away, or three weeks away, maximum. The others are a bit longer."
Wenger may play defender Gabriel Paulista, the January signing from Villarreal, who is "very close" to his debut.
"He likes to defend. It's more and more difficult to find people like that," he added.
"(He is) a player who has overall good qualities: good pace, good in the air, good in one against one.
"But it's best I don't talk too much and let him play and he shows how good he is."
