Oh boy Ive watched nearly every game over past 7 years, and several in person. He's playing average lately vs terrible before. He leads the league at SS with most errors, has so so, and accuracy is below average. It's obvious he doesn't have the hands like Espinal for example. If Bichette made that error that Semien did, would you be shocked, of course not, but when Semien did everyone was, so really cant compare the two on defense, Semien is consistently better. Ill give you he is getting better, so maybe he will become a good defensive SS consistently, only time will tell. It's possible he would make a better 2nd.