Britons Kyle Edmund and Heather Watson made their experience count to reach the second round at Wimbledon.
Edmund took his time to impose himself on Wimbledon debutant Jaume Munar in a 6-4 6-4 6-4 win, while Watson also made a shaky start against 17-year-old qualifier Caty McNally.
British number two Watson saved two set points in the first set before beating the American 7-6 (7-3) 6-2.
Edmund was error-prone in his win over resilient world number 90 Munar.
The British men's number one will face another Spaniard - former world number seven Fernando Verdasco - in the next round, while Watson takes on Estonian 20th seed Anett Kontaveit.
Edmund made to battle for victory
Edmund had come into Wimbledon after a confidence-boosting first Tour-level grass-court semi-final at Eastbourne last week.
But against Munar, the 24-year-old looked far from assured, going an early break down and later requiring 10 set points to eventually take the opener when the Spaniard sent a shot wide.
It was a similar story in the second where the 30th seed repeatedly hit long from the baseline and the tenacious Spaniard seemed to be able to get to impossible-looking shots.
Edmund had looked like would run away with the third, going 5-1 up before Munar won three games in a row.
There were encouraging signs that Edmund seemed unhampered by a knee problem that forced him to retire from his second-round match at the French Open, with the Briton racing forward for a drop shot in the seventh game of the second set and making a lob.
And he won back-to-back games to love with the perfect mix of forehand winners, an ace and a drop shot to show glimpses of the player who reached the 2018 Australian Open semi-finals.
But with 37 unforced errors - to his opponent's 20 - there were too many mistakes to back up his pre-tournament claim that he could win Wimbledon.
"I had to work hard for it for sure," Edmund said. "The guy was a really good fighter, he played with a lot of spirit.
"Hopefully I can improve from this match and make my life a little bit easier."
'Nervous' Watson pulls through
Watson, appearing in the main draw at Wimbledon for the 10th year in a row, came into the championships on the back of first-round exits at the grass-court events in Nottingham, Birmingham and Eastbourne.
She made a shaky start here, going 3-1 behind in the opening set before winning three games in a row to draw level.
There were eight breaks of serve in the first set and Watson made a desperate challenge on a McNally serve at 30-15 and 6-5 that the replay showed was well in and gave the American two set points.
But Watson unleashed a fantastic forehand down the line to save the first one and forced the American into a forehand error to save the second. To the delight of a packed court 12, she never looked back.
Another netted forehand by McNally sent it to a tie-break, which a pumped-up Watson raced through.
She kept up the momentum to go 5-1 up in the second, the only wobble coming when she needed four match points to wrap up the victory.
"I was a bit nervous today and I think it showed," said Watson, who has reached the third round three times here and won the mixed doubles title with Henri Kontinen in 2016.
"I'm a confidence player, so not having those wins in the last few weeks, I was maybe over-thinking a bit."
Watson is one of four Britons in the women's singles draw, with Johanna Konta, Katie Swan and Harriet Dart playing their first-round matches on Tuesday.
Murray's doubles partner 'feeling pressure'
While there are 10 British players in the singles main draws, the biggest home interest will be around former world number one Andy Murray's return to Grand Slam action in the men's doubles.
Imagine, then, being the 32-year-old Scot's doubles partner Pierre-Hugues Herbert and having to tell Murray you were feeling pain in one of your quads.
Except, he didn't tell him.
The Frenchman said he felt pain on Sunday but that it had gone during his first-round singles defeat by South African fourth seed Kevin Anderson 6-4 6-2 6-3 on Monday.
"I don't want to imagine me having to say anything to Andy about an injury," the 28-year-old said.
"I was scared for one of my quads. But when I did the medical tests [on Sunday], everything was fine."
He added that playing alongside Murray meant he was feeling "more pressure than ever".
"But it's something so special," he said. "I'm feeling lucky and I'm so motivated and pumped to play with Andy, and to have the luck to play with him here in Wimbledon."