In an eventful day in the tussle at the top of the general classification, Bevin and second-placed Impey both claimed five bonus seconds each in the intermediate sprints.
But Bevin crashed with nine kilometres to go, sporting rips to his jersey and cuts to his back and right arm; he was seen holding said arm and his right ribs after he crossed the finish line with the peloton after a heroic but pained effort to rejoin.
At the end of the stage in Strathalbyn, Ewan (Lotto-Soudal) was the fastest, beating 20-year-old Philipsen and stage three winner Peter Sagan (Bora-Hansgrohe).
But 25 minutes after the stage's conclusion, race commissaires reviewed the final kilometre of the race and decided to disqualify Ewan after overhead camera footage showed that he clearly head butted Philipsen three times in the final few hundred metres.
It meant that neo-pro Philipsen was awarded the victory, his first since joining the WorldTour ranks in the off-season from Hagens-Berman Axeon.
Bevin (CCC Team) goes into tomorrow's final stage that finishes atop Willunga Hill maintaining his seven second advantage to Impey (Mitchelton-Scott).
He went to hospital after the stage and will be hoping he is fit enough to hold off the expected challenge of third-place Luis Leon Sanchez (Astana) who is 16 seconds adrift, Richie Porte (Trek-Segafredo) and other stronger climbers tomorrow.
How it happened
As soon as the neutral zone finished and the 149.5km stage began, three riders jumped off the front to create a break: Jason Lea and Ayden Toovey of UniSa-Australia and AGR2 La Mondiale's Clement Chevrier.
They were only allowed to ride clear for 40km, though, as stage four winner Impey eyed the bonus seconds at the first intermediate sprint. His Mitchelton-Scott helped bring the trio back, and he duly won the sprint, with Bevin in second place, to go six seconds behind the race leader.
The peloton remained intact for the second intermediate sprint and this time the positions were reserved between Impey and Bevin, ensuring that the latter regained his seven second advantage on the general classification.
Their mid-stage battle over without any change to the standings, a new breakaway was allowed to form. Toovey returned to the head of the race, joining Matthieu Ladagnous (Groupama-FDJ). They lasted an hour and the peloton was back together with 34km left to race.
Crosswinds made the finale interesting for a number of riders who dropped back, unable to keep pace with Bora-Hansgrohe's and Team Sky's fast pace.
At nine kilometres to go, race leader Bevin came down in a crash at the back of the peloton. The New Zealander got straight up but appeared to be limping as he got back onto his bike.
He struggled to catch back onto the peloton but they slowed down in an effort to help him regroup; he settled back into the peloton with 1.5km to go. Meanwhile, Deceuninck-Quick-Step and Lotto-Soudal were in charge at the front, readying their sprinters.
Two right turns followed the kilometre-to-go inflatable, and Elia Viviani (Deceuninck-Quick-Step) had the perfect lead-out from teammate Fabio Sabatini. But he failed to press on and Ewan, riding fourth wheel behind Sagan, sprinted off to the right and passed the three in front of him.
The Australian was too fast for his challengers and despite a late charge from Philipsen on his left crossed the line in first place comfortably. Viviani would have been nightly disappointed to have squandered a great chance to add to his stage one victory.
Shortly afterwards, though, Ewan's win was stripped from him for his headbutts and it was Philipsen who was able to celebrate his maiden WorldTour victory, although its circumstances would not have been how he imagined such a feat.
Tour Down Under 2019, stage five: Glenelg > Strathalbyn (149.5km)
1. Jasper Philipsen (Bel) UAE-Team Emirates
2. Peter Sagan (Svk) Bora-Hansgrohe
3. Danny van Poppel (Ned) Team Jumbo-Visma
4. Jens Debusschere (Bel) Katusha-Alpecin
5. Elia Viviani (Ita) Deceuninck-Quick Step
6. Phil Bauhaus (Ger) Bahrain-Merida
7. Cees Bol (Ned) Team Sunweb
8. Ryan Gibbons (RSA) Dimension-Data
9. Wout Poels (Ned) Team Sky.
10. Davide Ballerini (Ita) Astana, all at same time
General classification after stage five
1. Patrick Bevin (NWZ) CCC Team, in 17-00-25
2. Daryl Impey (RSA) Mitchelton-Scott, at 7 secs
3. Luis Leon Sanchez (Esp) Astana, at 16 secs
4. Ryan Gibbons (RSA) Dimension-Data
5. Jan Polanc (Slv) UAE-Team Emirates
6. Ruben Guerreiro (Por) (Katusha-Alpecin)
7. George Bennett (NWZ) Jumbo-Visma
8. Chris Hamilton (Aus) Team Sunweb
9. Wout Poels (Ned) Team Sky
10. Michael Woods (Can) EF-Education First, all at 26 secs
Thank you for reading 5 articles this month* Join now for unlimited access
Enjoy your first month for just £1 / $1 / €1
*Read 5 free articles per month without a subscription
Join now for unlimited access
Try first month for just £1 / $1 / €1