The fourth Ashes test sprung to life late on Day 1 after sweeping showers threatened to dampen the prospects of both teams for a positive start at the Sydney Cricket Ground.
After rain delays permitted only 21 completed overs in the opening two sessions, runs and wickets came more frequently in the final passage of play after Tea as Australia reached 126-3 at Stumps.
Steve Smith was unbeaten on six and Usman Khawaja was four not out when rain ended play for the day.
Veteran seamer Stuart Broad, recalled to the England team after being omitted for the third test in Melbourne, went someway to vindicating his selection by dismissing David Warner and generally appearing the most threatening bowler in the England attack.
Harris and Warner put on 50 for the first wicket before Broad made the breakthrough for England in the 21st over, teasing Warner onto the front foot and finding the edge which carried comfortably through to Zak Crawley at second slip for his 527th wicket in 151 matches.
Warner, who made 30 with six boundaries off his 72 balls, swiped his bat through the air in frustration at his dismissal and not capitalizing after making another good start to an innings in this series.
It was the 8th time Broad (1-34) has captured Warner's wicket over the past seven Ashes tests that the fast bowler has played in.
Marnus Labuschagne joined Harris at the crease, but four balls into the 22nd over showers swept back over the ground forcing the players from the field after only 9 overs of play in the middle session, much to the disappointment of the crowd of about 30,000.
Play resumed shortly after tea and Harris and Labuschagne lifted the scoring rate, often finding the gap through cover for runs, and then clipping through square leg as the English bowlers over-corrected their line.
Harris made 38 but, like Warner, failed to capitalize on a good start as he edged a Jimmy Anderson (1-24) delivery through to England captain Joe Root at first slip to have Australia at 111-2.
Next over, Mark Wood (1-31) got a deserved wicket when his pace straightened up Labuschagne (28) on the crease and the world's top-ranked batsman feathered an edge through to wicketkeeper Jos Buttler.
It was an eventual finish to the day after Australia skipper Pat Cummins won the toss and elected to bat first on a green-tinged SCG pitch.
Both teams made one change from the third test at Melbourne where Australia won by an innings and 14 runs to take a 3-0 series lead and retain the Ashes.
For Australia, Khawaja replaced Travis Head, who was absent after testing positive for the coronavirus. Broad returned for the injured Ollie Robinson.
England has lost the series but is still aiming to take something from the tour by winning an Ashes test in Australia for the first time in almost a decade.
Brief Scores: Australia 126/3 (Marcus Harris 38; James Anderson 1/34) vs England