Arsenal club captain Per Mertesacker believes a cautious approach should be taken with Alexis Sanchez.
The Chilean ace scored a hat-trick in Saturday's 5-1 win at West Ham United to take his season tally to 11 goals in the Premier League.
Sanchez is often criticised for working too hard and not giving his body a rest but Mertesacker feels the medical team are doing their best to curtail his training habits and keep on the fresh side.
"He does whatever he wants to do in training and he's pretty much unpredictable," he said.
"At times I think we need to be cautious with him.
"He had an injury at around this time last year but the team we have here are doing a good job of making sure he is ready and fit to play."