Let p be an odd prime and let Jo(X), Jr(X) and Je(X) denote the
three different versions of Thompson subgroups for a p-group X. In this
article, we first prove an extension of Glauberman's replacement theorem.
Secondly, we prove the following: Let G be a p-stable group and P∈Sylp(G). Suppose that CG(Op(G))≤Op(G). If D is a strongly
closed subgroup in P, then Z(Jo(D)), Ω(Z(Jr(D))) and
Ω(Z(Je(D))) are normal subgroups of G. Thirdly, we show the
following: Let G be a Qd(p)-free group and P∈Sylp(G). If D
is a strongly closed subgroup in P, then the normalizers of the subgroups
Z(Jo(D)), Ω(Z(Jr(D))) and Ω(Z(Je(D))) control strong
G-fusion in P. We also prove a similar result for a p-stable and
p-constrained group. Lastly, we give a p-nilpotency criteria, which is an
extension of Glauberman-Thompson p-nilpotency theorem