He heard the Messenger of Allah ﷺ, when he raised his head from bowing, say, "Our Lord, to You belongs all praise."
حدثنا عبد الرزاق حدثنا معمر عن الزهري عن سالم
أنه سمع رسول الله ﷺ حين رفع رأسه من الركوع قال ربنا ولك الحمد
Its isnad is sahih. It is in fact part of the preceding hadith, as already noted in the narration of Malik from Zuhri 4674, and as in Muwatta 1:97, 98. See also Muntaqa 845.