Probably because he hasn't played a whole match in ages. He would have started otherwise.
Maybe Pochettino was sentimental and thought Son scored 2, has the most CL experience in our team bar the CB's.
This bigger pitch stuff seems to keep coming up. Nobody says it when we play teams in the PL on same size pitches and beat them.
Totti quoted all those games:
Spam away small pitch
Chelsea away Small pitch
Woolwich home small pitch
Southampton home small pitch
WBA home small pitch
Newcastle away small pitch
How come nobody blamed small pitches?
Man city away. won big pitch Biggest pitch in PL
Man U away, should have won big pitch
Everton away big pitch won
Villa away big pitch won
Woolwich away big pitch drew
Southampton away won big pitch
Then when we lose at Wembley is pitch size.
Newcastle's pitch is pretty much the same size City, Man Utd and Southamptons and Aston Villa - Obviously, the level of competition comes in the way too. Aston Villa are fucking dogshit, so regardless of pitch size I'd expect to beat them.
Everton's is barely any bigger than ours. It's funny, I always look forward to the likes of Everton, Stoke, Palace, Leicester away etc who's pitches are all small as opposed to when we go to Old Trafford, Etihad, Emirates where I feel those teams keep the ball a lot better than us or have good records against us.