The 3-3 stalemate at Hillsborough took many by surprise given the Owls’ transfer business during the summer and the 4-0 win they secured against the Blues on the final day of last season just three months ago.
But in truth, Pompey will have been disappointed with just a draw as Danny Cowley’s new-look battling side came within minutes of securing a huge victory on day one of the new term.
The Blues, nevertheless, put down an important marker for the challenge ahead and will no doubt have made others in League One sit up and take notice.
Cowley admitted before a ball was kicked in Yorkshire that he was happy to go into the season under the radar.
Well, that won’t happen now given the result at Hillsborough.
But what do the bookies’ think now about the race for promotion from the division and, in particular, the Blues’ chances of reaching the Championship?
Well, we checked in with SkyBet to see exactly just that with day one of the new campaign now out of the way.
Here's what he discovered.
1. Morecambe - 80/1
IN: Donald Love (Salford, free), Farrend Rawson (Mansfield, free), Max Melbourne (Lincoln, free), Caleb Watts (Southampton, loan), Connor Ripley (Preston, free), Jack Taylor (Port Vale, undisc), Ash Hunter (Salford, free), Jensen Weir (Birghton, loan).
OUT: Aaron Wildig (Newport, free), Jordan Ayunga (St Mirren, free), Kyle Letheren (Hartlepool, free). Photo: Clive Rose
2. Fleetwood - 50/1
IN: Jay Lynch (Rochdale, free), Shaun Rooney (St Johnstone, undisc), Brendan Wiredu (Colchester, undisc), Callum Morton (West Brom, undisc), Josh Earl (Preston, free), Promise Omochere (Bohemians, undisc).
OUT: Jordan Rossiter (Bristol Rovers, undisc), Brad Halliday (Bradford, free). Photo: Alex Livesey
3. Cheltenham Town - 40/1
IN: Dan Adshead (Norwich, undisc), Tom Bradbury (Halifax, free), Dan Nlundulu (Southampton, loan), Shaun MacDonald (Torquay, free), Taylor Perry (Wolves, loan), Luke Southwood (Reading, loan), Caleb Taylor (West Brom, loan), James Taylor (Bristol City, loan), Ryan Jackson (Gillingham, free).
OUT: Will Boyle (Huddersfield, free), Owen Evans (Walsall, undisc). Photo: Harry Trump
4. Exeter - 33/1
IN: none. Jamal Blackman (Huddersfield, free), Kegs Chauke (Southampton, loan).
OUT: George Ray (Barrow, free). Photo: Pete Norton