Had he not blocked those pitches it would have been his error, there is almost no way they could not be blocked.
Problem for him and Sanchez, if they keep doing that knee thing, had the batter been a on the other side and the pitch on the other side, there is zero way it would have been blocked.
His double made huge difference, but as it is - Sanchez is at .216 with 8 rbi and Jeffers is at .152 with 0 rbi.