On Tuesday, Davis informed teammates of his intentions to leave the club and take up a lucrative offer - believed to be worth as much as $4 million over five years - with newcomers, GWS.
Bickley said the players were shattered by the 20-year-old's defection.
"Monday was a bit of a shock to the players," he said on Thursday.
"A lot of them didn’t know Phil was in negotiations with [GWS] or whatever he'd been doing.
"They're disappointed. They would've loved Phil to stick around and they realise he's a quality person and quality player.
"We'd always factored him into our future plans. To have him leave I guess leaves a bit of a hole, but at the same time it creates an opportunity for another young player to step up and fill that position."
A season-ending shoulder injury meant Davis was able to inform Adelaide of his plans to join the Giants when his mind was made up, without fear of being ushered out of the club and barred from selection for the remaining games of the season, as was the case with Gold Coast recruit Nathan Bock last year.
The timing of his announcement suits the Crows, who can start planning for the future without him, but has raised eyebrows in the wider football community.
Under AFL rules regarding contracted players, GWS is unable to agree to terms or reach any arrangement with a player or his management during the season.
Giants chief executive Dale Holmes issued a press release following Davis' bombshell, confirming the club had held talk's with the 20-year-old's management, but saying no agreement between the parties had been reached.
Collingwood president Eddie McGuire accused GWS of "cheating" by securing Davis, and encouraged the AFL to launch an investigation into whether the club had gone outside the rules.
Bickley refused to buy into the debate, saying he wasn't familiar with the rules, but admitted there might be a "grey area".
"Every club has players coming out of contract and every list manager wouldn't be doing his job if they weren't looking at opportunities and recognising what type of players they want and trying to secure them," he said.
"I would suspect that player managers and recruiting people talk. Whether that's classified as approaching people out of contract I'm not sure.
"There's probably a grey area there and I'm sure people exploit that."
Davis' departure opens the door for young defender Daniel Talia, who has showed promise in four appearances this season.
The Crows, who selected Davis and Shaun McKernan with their first two picks in the 2008 NAB AFL Draft, were criticised for selecting another key-position player in Talia with their first-round pick in 2009.
However, the club's decision to recruit Talia has already paid off, having lost two centre half-backs in the space of 12 months.
"Daniel's progressed really well. He was always going to push up and challenge for those spots," Bickley said.
"The longer-term picture was perhaps that Daniel would be more of a [full-back to replace] Ben Rutten when Ben's time [to retire] arrived.
"Thankfully, that looks to be a fair way away with the way Ben's going about his business, and now we need Daniel in a different position."
Forgotten defender Tony Armstrong has been rewarded for his good form in the SANFL, being included in the 25-man squad to play the Brisbane Lions at the Gabba on Sunday.
There's only one confirmed change to the team that beat Port Adelaide, with injury-hit midfielder David Mackay forced back onto the sidelines with a knee complaint.
It was also bad news for defender Matt Jaensch, who will have a reconstruction on his injured shoulder next week.
The Crows responded to the resignation of long-serving coach Neil Craig, and a disastrous 103-point loss to St Kilda with a determined 32-point win over the Power last weekend.
Bickley said the challenge for his team would be to replicate that effort against the Lions.
"It's a big game for us because you hear people judging our performance last weekend [and saying] you can't take much from that … because with a change in coach and on the back of a poor performance there was always going to be a response," he said.
"A lot of people have discounted last week and are keen to see what we do this week.
"There was some emotion last week and some blokes had their pride pricked after the performance against St Kilda.
"Now things have settled down a bit we need to know we can count on them to produce a really strong performance again."
Katrina Gill covers Adelaide news for afl.com.au. Follow her on Twitter: @AFL_KatrinaGill
