I dont think there has ever been a power struggle between GCMT and SMA, indeed GCMT invited SMA 'round the table' but nothing came of it. GCMT comprises of 11 professional associations, of these the majority have sports massage members, totalling around 8,000 therapists (plus another 17,000 who do other types of massage.
It is true that the SMA, did have a good footing in professional sport, however, this does not seem to be the case anymore (even if SMA were around, which they dont seem to be), the sporting governing bodies have realised that the discriminatory policy they had, using only SMA members (some poorly trained), was potentially very damaging.
Now that GCMT have accepted Sports Therapy, as a profession in its own right, into the fold, so to speak, we shall be seeing a lot more 'GCMT affiliated' (for want of a better word) therapists working in professional sport.