Implied Question: The Gemara, which states in Perek Shevu'as ha'Eidus (Shevu'os, Daf 33b) that, according to Rebbi Elazar b'Rebbi Shimon, we do not find a case of self-admission that is Patur, unless there are no witnesses at all ...

Answer: ... goes according to Shmuel.

Explanation #1: Rashi explains - 'You upset the Talmidim in the Beis-ha'Midrash, by saying something that is incorrect, seeing as Rav Huna, who is acquainted with Rav's sayings, and who is greater than you, does not hold of this distinction' ...

Question: Wherever 'Kipu'ach' appears, it is an expression of 'defeating' (in an argument).

Example #1: ... such as 'They are coming to overwhelm me with Halachos', in the second Perek of Kidushin (Daf 52b) and in Nazir (Daf 49b) ...

Example #2: ... and such as 'I defeated the three ordained Rabbis by mistake' (in Gitin, Daf 29b).

Explanation (Text) #2: The Rashbam therefore explains that we do not have the text 'Amar leih Rava', but simply 'Amar Rava, Kapachtinhu le'Sabi de'bei Rav' ...

Explanation #2 (cont.): ... which means that he defeated Rav Hamnuna, who is synonymous with 'Sabi de'bei Rav', and proved to him by virtue of the words of Rav Huna, who was better acquainted with the sayings of Rav than he was, that one cannot draw the distinction that he did'.

Proof: And he supported his explanation with the Gemara in the first Perek of Sanhedrin (Daf 17b [See Tosfos there, DH 'Ela']), which states 'Amri bei Rav, Rav Huna', on which it asks 'But did Rav Huna not say "Amri bei Rav"? To which it answers 'Rather say "Rav Hamnuna". And that is why he is called 'Sabi de'bei Rav'.

Question #1: Firstly, he erases the accepted text 'Amar leih'?

Question #2: Secondly, it is not the accepted thing to state 'Itmar Nami', with regard to a statement that has already been refuted?

Question #3: Thirdly, both the Mishnah and the Beraisa bear out Rav Hamnuna, as the Gemara will say shortly, whereas according to Rav Huna, Rav's opinion is refuted by the Mishnah?

Explanation #3: The explanation must therefore be - 'Amar leih Rava, "Kipachtinhu le'Sabi de'bei Rav" - meaning that Rava said to Hamnuna that he defeated Rav Huna, who is synonymous with 'Sabi de'bei Rav', who did not know to make the distinction that he made.

Explanation #3 (cont.): And in Sanhedrin, Rabeinu Tam explains 'Eima Rav Hamnuna' to mean - 'Do not say "Amar Rav Huna, Amri bei Rav", but "Amar Rav Hamnuna Amri bei Rav" '.

Proof: And so it is implied that in fact 'Amri bei Rav' is Rav Huna ...

Source: ... since in 'ha'Areil' (Yevamos, Daf 83b [See Tosfos there DH 'Amri']) the Gemara says 'Who is bei Rav? - Rav Huna, and Rav Huna says "Ein Halachah" '.

Refuted Explanation: Rashi there pushes to explain that when the Gemara says in Sanhedrin 'Say Rav Hamnuna', that speaks specifically where it is evident - where Rav Huna who says 'Amri bei Rav', only then is it Rav Hamnuna.

Refutation #1: In that case, when the Gemara says in Sanhedrin that 'Shalchu mi'Tam' is Rebbi Yossi b'Rebbi Chanina, and 'Mechku aleih be'Ma'arva', Rebbi Elazar, and in reply to the query that this is disproved from the fact that we find 'Shalchu mi'Tam according to Rebbi Yossi b'Rebbi Chanina', it replies that we must switch the two titles ...

Refutation #1 (cont.): ... why did it not answer 'Where it is evident is different'?

Refutation #2: Moreover, it is not at all plausibe for Rav Huna to quote Rav Hamnuna, who was his Talmid's Talmid ...

Source: ... as is implied at the beginning of 'ha'Dar' (Eruvin, Daf 63a).

Conclusion: But this is not the place to elaborate further.

Question: Why does Rav Ashi not cite the Mishnah in the last Perek of Shevu'os (Daf 49a)

Question (cont.): Because above (on Amud Alef) it is clearly justified in citing the Beraisa ...

Reason: ... since it needs to learn something from Rebbi Elazar b'Rebbi Shimon in the Seifa, which is not mentioned in the Mishnah in Shevu'os ...

Question (concl.): ... whereas here it does not need to learn anything from th Seifa?

Answer: He knew that regarding the Mishnah in Shevu'os, one can counter that that is precisely what it is coming to teach us, as the Gemara will say shortly, but regarding the proof from the Beraisa, which adds to the Mishnah, he figured that it is coming to teach us that the confession of Tevichah is not considered a confession.