The 60-cap veteran and Champions League winner returned to the Three Lions side in the final game of the group stage, coming on at half-time against the Czech Republic to partner Phillips in midfield.
Henderson has enjoyed Phillips' emergence as an important part of the national team on and off the pitch.
"Kalvin's a very good player, you've seen that in the games he's played not only for Leeds but for England " said the 31-year-old.
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"He's done fantastically well and he's a brilliant lad to have around.
"He's been a big player for us but we've got a lot of good players in midfield - Dec [Declan Rice], who's been brilliant, Jude [Bellingham], who's a fantastic talent who's done brilliantly this season and when he's come on, Mason [Mount], there's a lot of talented players in the midfield area so we keep pushing each other every day in training but we also get on really well off the field, which is important."
Much of the debate about Gareth Southgate's midfield since Phillips made his international debut last September has pitted the Whites man against both Declan Rice and Henderson for a starting role.
Before the clash with Czech Republic there were also calls for Bellingham to start in the middle.
But Southgate has preferred to play Phillips alongside Rice, either as a defensive midfield pairing or, since the Euros began, with the latter holding and the former in a more advanced role, patrolling the right hand side of the pitch predominantly.
When Henderson replaced Rice on Tuesday night at Wembley, Phillips dropped deeper and the more experienced man took up a position further forward.
Henderson's return to fitness following groin surgery and the 45 minutes he played in midweek gives Southgate another option to change his midfield from the start when England face Germany in the last 16 next Tuesday.
Whether or not Phillips, the only England outfield player to feature for every minute of every game thus far, gets the nod from the manager again, he's got Henderson's backing.
"Whatever team the manager decides to play I'm sure we'll give it absolutely everything and it will be the right balance within the midfield," he said.
"Kalvin's been a big part of that and he will be in the next game and throughout the tournament."