The Whites’ halted a run of back-to-back defeats and in turn ended the Magpies’ momentum as Eddie Howe’s side returned from the World Cup break with wins over Bournemouth and Leicester City in the Carabao Cup and Premier League.
Meslier made a string of fine saves at St James’ Park but fine defensive work in front of him meant he was rarely relied upon as the last line of defence.
"I'm always challenging him to mature with his presence in goal, with his belief in himself with himself, with his assuredness in decision making and with saves and with crosses," said coach Marsch.
"For me, by being the last defender at the right time, the choices he made with the ball, the saves he made, the crosses that he caught, this is probably his best performance since I've been here, even with Liverpool.
"I think we're seeing it, seeing a goalkeeper that's growing right before our eyes and that's going to be really important for us."
The Frenchman makes the cut in the latest Premier League team of the week, based off WhoScored ratings, alongside an Arsenal trio and Brentford pair. Newcastle, Manchester United, Fulham and Aston Villa players also feature...
1. Illan Meslier - 8.1
The Frenchman made five saves at Newcastle to earn his third clean sheet of the Premier League season. Photo: LINDSEY PARNABY
2. Kieran Trippier - 8.1
The Newcastle man is a regular presence in the weekly best XI. He made six key passes against Leeds as he proved one of the Magpies' most creative outlets. Photo: LINDSEY PARNABY
3. Liam Cooper - 7.6
The Leeds centre-back made four tackles, three interceptions and six clearances as the Whites earned a hard-fought point in Newcastle. Photo: George Wood
4. Ethan Pinnock - 7.6
Played his part in Brentford's win over West Ham with an incredible 14 clearances at the London Stadium. Photo: Charlotte Tattersall