UEFA have admitted they are "slightly worried" about the appearance of the pitch on which Wednesday night's Champions League final will be played - but they do not believe it will hamper the all-English match.
A second pitch was required after the initial one, placed on top of the 'plastic' surface that is normally used at the stadium last October, was deemed unacceptable.
UEFA officials are happy that the pitch will be playable, but spokesman William Gaillard told BBC Sport: "We are slightly worried about the look of it.
"In terms of the quality, we have made some tests in the last few days and it is perfectly fine.
"It may not look very, very green on television, but, essentially, it is a good pitch to play football on. At this stage, we are confident it will be fine."
Frost is relieved that he managed to talk stadium bosses into spending £160,000 on a second grass surface, adding: "If I hadn't persuaded them, they would have used the old one which would have been a catastrophe."