Barry Zito has never had a season where he pitched less than 210 innings, exception 2000, when he made 14 starts.
Just once has he had an ERA over 4, in 2004. That bloated his career ERA to a great 3.54. His record is 101-62. He knows how to win.
He has arguably the best curve in the game.
He will be 29 next year.
He won the 2002 Cy Young.
His career Opponent's Average is .232
All in all, if given to me, I would take him. Matsuzaka is unproven in the big leagues, and who knows about that "gyroball". If they were the same price in total, I would take Barry Zito. If Zito is more expensive,maybe I will change my mind.
As for against the Yankees, he has pitched 14 1/3 innings. Maybe he sucks, maybe it is a small sample size. He usually has a bad April, this year's start vs them was in April. The other time, he pitched VERY well:
6 innings, 5 hits, 1 ER, 4 BB, 4 K, 10 GB, 4 FB
He pitched again vs the Yankees, and was mediocre.
7 innings, 4 hits, 5 ER, 7 BB, 4 K.
One good, one mediocre,leaning towards bad, one BAD. You never know. The Yankees do not own Zito though.