Moeen Ali's display against South Africa at Lord's a watershed moment - Bayliss

Moeen Ali's match-winning performance in England's first Test against South Africa at Lord's could be a "watershed" moment, says coach Trevor Bayliss.

Moeen took 10-112 with his off-spin to add to the 87 he scored with the bat in the home side's 211-run win.

Previously England's number one spinner, Moeen was joined at Lord's by the slow left-arm of Liam Dawson.

"We selected him as a batter who bowls a bit," said Bayliss. "Maybe that has taken the pressure off."

On a pitch that offered great assistance to the spinners, Moeen claimed 6-53 on the fourth day as South Africa were bowled out for 119 in their second innings.

"It was a good wicket for him to bowl on but the more it happens for him the more confidence he will get," Australian Bayliss told Test Match Special. "Hopefully it is a watershed moment for him."

Worcestershire's Moeen, 30, has batted in every position from one to nine for England as well as often being the sole spinner in the side.

In 2016 he made four Test centuries, more than any other England player, but his bowling average has declined year on year since his debut in 2014.

However, in this Test he passed 2,000 runs and 100 wickets, the second fastest England player to complete such a double after Tony Greig.

"It was great to see him be so aggressive when he got the chance to bowl in both innings," said England captain Joe Root. "He and Ben Stokes give us great depth."

Root was leading England for the first time since replacing Alastair Cook as Test captain in February.

The skipper made 190 in the first innings to help England end a six-match winless run.

"Everyone has played their part," said Root. "There were some crucial periods where guys showed a lot of character, read the situation well and were proactive in the way they went about it.

"I wanted us to stay ahead of the game and for players to take responsibility if they were in a position to do so. I think everyone at certain points did that and it's important we continue that if we are going to move forward."

Meanwhile, South Africa coach Russell Domingo has once again left the tour to be with his mother, who is seriously ill.

The second Test at Trent Bridge begins on Friday, with England set to name their squad on Monday.