Commentary for Kiddushin 134:7

If you say that the mishnah accords with R. Yehudah who said that a convert may not marry a mamzeret, then the mishnah works well. The words “in any case” come to include an Israelite who marries a halalah (the child follows the father and is not a halal) and the case of the second generation Egyptian who marries a first generation Egyptian. The words “this is the case” exclude the cases of Ravin and R. Dimi from above.