Against Southampton last week Phillips and captain Liam Cooper made their first appearances for the Whites since injuring hamstrings against Brentford in December, when Marcelo Bielsa was still the coach.
Having suffered no reaction, both can be expected to play in today’s important Premier League match at Watford.
Centre-back Cooper was selected to start last week with Marsch of the view it had to be one or the other because neither would be able to play the full 90 minutes. As it turned out, Cooper did when an error saw Leeds replace the wrong player for their final substitution.
But England midfielder Phillips showed the quality of his passing in particular after coming on for the final 24 minutes.
“Both will have a big effect on our group on the pitch and off,” said Marsch
“Liam, I thought, put in a courageous 90-plus-minute performance and was one of our best players. He matched tactically what we want from the game, which I think in his first run-out was really impressive for him to adapt so quickly and easily.
“And then to have Kalvin on the pitch, I think everybody saw it brought poise to our group, he helped settle the game down.
“I heard him say after the game that he didn’t do much but just by being on the pitch for us, I think that presence meant a lot.
“It’s really great to have those guys back and we used this week to get them nearer and nearer to 100 per cent.”
Although Marsch has spoken previously about how Mateusz Klich can play further on, the form of Rodrigo in the hole means a start for Phillips is likely to see the Pole or Adam Forshaw on the Vicarage Road bench. Robin Koch, who can also play as a holding midfielder or as a centre-back has been impressing in training and Marsch wants that to count for something.
“I’m a big believer that training means something and so I’m on top of it,” said the American.
“There’s different kinds of managers. There’s some managers that run everything, there’s some managers that don’t run anything and just watch to try to evaluate how players are performing.
“Right now, we’re certainly in a phase where I need to be on top of training because I am really reinforcing the behaviours we need every day but I have an eye that I can also evaluate how guys are training and who is grasping concepts at the fastest rates.
“Robin Koch has performed very well in training and he hasn’t always been rewarded with decisions on matchday. But I am very much aware that when we need him, we need to think carefully about how to use him more on gameday so his performances mean something.
“Then (team selection)’s about looking at the opponent every day and thinking about what’s the best formation, what’s the best group, how do we use all the tools that we have available, players, qualities and everything, to give ourselves the best chance to perform and win games?
“My job is to do all of those things and then make sure I reinforce with the player group and the team as a whole that I believe in them and I am helping them understand how to get better as individuals and as a group.”
This could be an important weekend in the Premier League relegation battle. Everton play first, at home to Manchester United at 12.30pm, knowing victory could put them two points behind Leeds from one fewer game. On Sunday Burnley will look to build on defeating Everton in midweek by winning at bottom-placed Norwich City to take them to 27 points.
It means there will be pressure on Leeds to add to their 30 points at 3pm against a Watford side whose position will be even more precarious unless they can increase their 22.
After today, Leeds complete their season with matches against Crystal Palace (away), Manchester City (home), Arsenal (away), Chelsea, Brighton and Hove Albion (both home) and Brentford (away).