The sportswear giant has already been experiencing a significant slowdown in production due to the closure of factories in Vietnam, with a lag of potentially four months. The south-east Asian country normally accounts for 28% of Adidas' total production.
While the company had made contingency plans for this, The Independent has been told that the signing of Ronaldo has changed the sitiation and a drop-off is expected. While United are adamant that the signing is about what the Portuguese can bring on the pitch, they are naturally conscious of the demand for kits as a consequence.
An Adidas spokesman told The Independent: "We are working in collaboration with MUFC to try and meet exceptionally high fan demand for our new designs but expect low availability of certain products."
Meanwhile, Ronaldo has been given the opportunity to join up with his new teammates earlier than expected after being released early from the Portugal squad after firing them to World Cup qualifier victory over the Republic of Ireland in dramatic fashion.
The 36-year-old scored a world record 110th international goal to cancel out John Egan's opener with just a minute remaining at the Estadio Algarve on Wednesday evening, and then completed the job with his 111th in stoppage time to seal a 2-1 win.
However, after removing his shirt in celebration, he was cautioned by Slovenian referee Matej Jug and having been booked earlier in the campaign, is suspended for Tuesday night's trip to Azerbaijan.
Ronaldo's release means he will also not feature in Saturday's friendly against World Cup hosts Qatar in Hungary, freeing him up to travel to England earlier than planned.
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