I thought this comparison was interesting, so I had to look it up. Sonny Gray's (top) age 33 season vs Santana's age 34 season. A couple things stand out to me: 1) Gray's 312 ERA+ YTD is almost certainly unsustainable, 2) his career ERA+ of 120 is quite a bit higher than Santana (101), and 3) B-R has Gray at career WAR of 26.9 vs Santana 27.0.