Rondon was a success in his only season on Tyneside, scoring 11 goals to help Toon fight off relegation.
And it was his battles with skipper Lascelles that impressed Ritchie.
"He changed our team completely," he said.
"That season we got a lot of stick but it was a success, we were solid, compact and never got beat by more than one or two.
"This guy came in and just gave us an outlet - we could chuck it down the channel, flick it to his feet or wherever...cross it from deep, this guy was on the end of it causing havoc, and creating chances.
"Ayoze Perez was one who I wanted to get in the team [Ritchie was picking his top XI] but he didn't make it, but them two up front complimented each other so well.
"Ayoze is lightweight but tactically aware of getting in the pocket and finding space. He and Ronny just clicked and towards the end of that season, they probably scored 15 goals between them and a few assists as well.
"They were pivotal for the success that season and Ronny was the main figurehead for that."