Constable Stew Thomas said Morris appeared unconscious in the driver's seat, without a seatbelt on, and with the window down when he approached.
It took up to 10 seconds to rouse him, the witness said.
The defendant's black Ford Ranger, parked opposite Rialto Cinemas, had mounted the kerb and hit a parking meter.
Officer in charge of the case Constable Olivia Scott said Morris was compliant at first but became more "hostile" after failing a breath test.
An evidential analysis at the station found he had a breath-alcohol level of 742mcg — nearly three times the legal limit.
"He changed to be a bit more difficult to deal with and this continued right through," Const Scott said.
Morris, part of the Otago squad's leadership team last season, explained to police that he had been drinking at a nearby flat and had got into his vehicle a couple of hours earlier to get warm.
He suggested he must have inadvertently bumped the gear stick of the automatic into drive which sent him forward a couple of metres, causing the accident.
"I tried to explain I'd been over the road and come to sleep in the car. I told them numerous times but I think it just went over their head," he said.
Morris put his perceived hostility down to the fact that police did not appear to be listening to his version of events.
The defendant — a midfield back who recently spent time in the United States playing rugby — said that the day before the incident, he had attended an arduous pre-season training session with the rest of the Otago squad.
The players had done seven hours of hiking, ending at Forsyth Barr Stadium.
Morris said he had later attended the team's official launch party at an Octagon bar where players mixed with sponsors for beer and nibbles.
The defendant and others went briefly to the casino before rejoining the squad at another central Dunedin bar.
"The boys were buying a couple of rounds and we had a few drinks there," Morris said.
"That's when the drinks were mixing."
He told the court his friend, Sefo Muasika, a doorman at the bar, was enlisted as sober driver and they picked up alcohol before heading to the Moray Pl party.
Morris rated his intoxication level as "six out of 10" when they got to the flat.
After downing pre-mixed vodka drinks, he had no memory of leaving.
Police prosecutor James Collins suggested Morris had got into the ute and put it in drive, planning to head home, before passing out.
The defendant admitted it was a possibility but thought it more likely he had turned on the engine to use the heater, then nudged the gear stick in his sleep.
"Did you intentionally drive?" his counsel Lisa Preston asked him.
"No I did not," he replied.
Ford vehicle expert Matthew Greene accepted if the vehicle had been turned on and left in neutral it would have only taken a small movement with minimal effort to move it into drive.
How far it would have lurched forward would depend on the gradient of the slope and how well engaged the handbrake was, he said.
