Leeds United and Middlesbrough played out a draw at Elland Road on Friday.
Clayton was in action for Middlesbrough against Leeds away from home at Elland Road in the Championship on Friday evening.
The 29-year-old midfielder, a former Leeds player, was superb for Boro, as the match ended in a goalless draw.
The former England Under-20 international was impressed with the performance of Saiz for Leeds.
The 27-year-old, who can operate as an attacking midfielder or as a forward, started the match for the Whites and played for the entire 90 minutes.
The Spaniard joined Leeds from Huesca in the summer of 2017 for a transfer fee reported by The Yorkshire Evening Post to be worth £3 million and is hugely popular among the Elland Road faithful.
Clayton has been on the books of Middlesbrough since the summer of 2014 when he moved from Huddersfield Town for an initial transfer fee reported by Gazette Live to be worth £1.5 million.
“Saiz is very, very good and movement-wise he is one of the toughest players I’ve ever been up against,” Clayton told Gazette Live.
Quality footballer
Saiz is one of the best and most creative players in the Championship, and the Spaniard will be a key player for Leeds this season.
The Spaniard scored five goals and provided seven assists in 28 Championship starts for Leeds last season, according to WhoScored.
So far this campaign, the 27-year-old has provided one assist in six Championship starts for the Whites, according to WhoScored.
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