You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
FA_Cup

Context:
The FA permitted artificial turf (3G) pitches in all rounds of the competition from the 2014–15 edition and beyond. Under the 2015-16 rules, the pitch must be of FIFA One Star quality, or Two Star for ties if they involve one of the 92 professional clubs. This followed approval two years previously for their use in the qualifying rounds only - if a team with a 3G pitch progressed to the competition proper, they had to switch their tie to the ground of another eligible entrant with a natural grass pitch. Having been strong proponents of the surface, the first match in the proper rounds to be played on a 3G surface was a televised first round replay at Maidstone United's Gallagher Stadium on 20 November 2015.

Question:
What happens if the pitch is not up to par? 

they had to switch their tie to the ground of another eligible entrant with a natural grass pitch.