Forty femtosecond pump and probe investigations in the 870 nm absorption band of the reconstituted core antenna, LH1, from Rhodobacter sphaeroides, in which varying amounts of Ni-bacteriopheophytin replace part of the native bacteriochlorophyll, show a tremendous shortening of the ground state recovery time with increasing amount of exchanged pigments. In the Ni-bacteriopheophytin containing antenna, a 60 fs deactivation channel has been found, which originates from a one-exciton state delocalized over the whole LH1 of about 20 pigment molecules. The 60 fs channel is interpreted as internal conversion in Ni-bacteriopheophytin.