I did not hear the Messenger of Allah ﷺ say anything about the phrase "they claim." He replied, "I heard the Messenger of Allah ﷺ say, 'What a wretched mount for a man is the phrase they claim.'"
حدثنا أبو بكر بن أبي شيبة حدثنا وكيع عن الأوزاعي عن يحيى عن أبي قلابة قال قال أبو مسعود لأبي عبد الله أو قال أبو عبد الله
ما سمعت رسول الله ﷺ يقول في زعموا قال سمعت رسول الله ﷺ يقول بئس مطية الرجل زعموا
Sourcing, [sahih] Ahmad narrated it, 5/401, from Waki, with this wording, and it is in Musaf Ibn Abu Shayba, 8/448, 449. Abu Qilaba stated explicitly that he heard it from Abu Abdullah, as recorded by Abu Naeem in Marifat Sahaba, 5/2949, hadith no. 6885, and the hadith has corroborating narrations.