Major League Baseball Question

[Joe Biden 2020]

I have a question about Major League Baseball, specifically pitching:

I know a starting pitcher has to go 5 full innings to get credit for the win, provided the lead is maintained by the bullpen the rest of the way.  Let's say a starting pitcher goes fewer than 5 full innings, but has the lead at the time of his exit.  If the bullpen maintains the lead the rest of the way home, how is the winning pitcher determined among the bullpen?

Any baseball fans are welcomed to chime in here.

[Gass3268]

I think its the relief pitcher that completed the 5th.

[Joe Biden 2020]

I think its the relief pitcher that completed the 5th.

Ok, that's what I was thinking, but that question has always been with me.  Thanks.

[Хahar 🤔]

The official scorer chooses the relief pitcher whom he deems to have pitched most effectively.

Rule 10.17(b):

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Emphasis mine.

[King]

These Chinese ESL textbook questions are getting really difficult.