Interesting article on why Price was left in for 50 pitches in game 4 - http://www.sportsnet.ca/baseball/mlb/stroman-not-price-is-simply-blue-jays-best-right-now/
an excerpt from the article:
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.The truth is, the Blue Jays – Gibbons in particular – decided that Stroman was going to be their Game 5 starter some time in the third inning of Game 2, when Stroman started to carve up the Rangers after Price did not get a single swing and miss on his fastball in a Game 1 loss to the Rangers – an alarming occurrence that led one Blue Jays executive to suggest off-the-record that Price looked "gassed." And with Aaron Loup not available and Price not used to being warmed up, sat down, and warmed up again, Gibbons resolved to go with Price as long as he could once he put him in Game 4.
Fact is, had Price not run into trouble in the eighth, he might have finished it off.
Stroman isn’t starting because Gibbons is a fan of the narrative; he is, simply, the Blue Jays best starter right now, with the best stuff.
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Pretty much confirms what some of us thought. Gibbons didn't want to use David Price in game 5 and that was the reason for pitching him to the point of exhaustion in game 4. In my mind, it also indicates why Gibbons took Dickey out with only one out left in the 5th inning and put Price in - Gibbons needed a good excuse to pitch David Price in game 4. So replacing Dickey with Price had more to do with eliminating Price from game 5 than needing him in game 4.