Mertesacker excited meeting up with new Arsenal teammates
The former Werder Bremen captain has been on international duty since the deal went through and has therefore only had a very fleeting glimpse of his new surroundings when he jetted in and out for a medical last week.
After "saying my goodbyes to individuals to whom I have a lot to thank", he will fly out to London for the start of his new adventure later on today and he admits it will be emotional.
"It is exciting," he added to Germany's dpa agency. "It is a new phase in my life and I am really looking forward to it, but I also feel nervous.
"It is like before the first day at school.
"Now I have a new challenge in a new country, a new style of play and a new language and I am ready for it."
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