In preseason, Lascelles revealed Watts has 'blown everyone out of the water' during the running sessions as he praised the youngster's character.
"We've been doing 1,500 metre runs, five times, as fast as we can," the Newcastle captain told NUFC TV.
"In fairness to the young lad, Kell Watts, he has just smashed everyone there and got the best time.
"My money was on Miggy but Kell has just blown everyone out of the water.
"He is a great pro, he is a great character and he understands his position. He understands he has got to reach a certain level.
"Some of the younger lads nowadays play a couple of games, get in the papers and think they have made it but Kell has been out on loan, he knows what it is like down at Stevenage and at Mansfield and he is always looking to improve his game.
"He is always talking to the senior players and he has got a great character.
"It is refreshing to see and he is pushing us. He is a great credit to the group."