They spent two years in the trenches at Crystal Palace.
They spent the summer training together on a 4G pitch in Surrey.
But on Saturday, Gary Cahill and Scott Dann will go hell for leather in opposition when AFC Bournemouth face Championship rivals Reading.
The pair left Selhurst Park within a fortnight of each other, Cahill signing for the Cherries in mid-August and Dann joining Reading just ten days later, both as free agents.
Dann, 34, spent more than seven years at Palace, netting 13 goals in 164 appearances in the Premier League having previously played in the top flight for Birmingham and Blackburn.
Before they became team-mates, they regularly locked horns, their first duel coming when Cahill’s Bolton triumphed 2-1 against Dann’s Birmingham at St Andrew’s in September 2009.
Dann gained revenge when a John Terry own goal earned Palace a 1-0 win over Chelsea in March 2014, the current scoreline between the two standing at 4-4.
Something of a Cherries nemesis, Dann has scored four goals in his past five games against them, all for Crystal Palace in the Premier League.
Discussing his relationship with Dann, Cahill told afcb.co.uk: “Scott lives close to me, we’re good friends and I got on very well with him when I was at Crystal Palace.
“I’ve played against him numerous times during my career and we crossed paths in the Premier League and then played together for two years.
“I’m delighted to see him back up and running. When I spoke to him at the start of the season, he had a little niggle and it looks like he’s come through that.
“He scored for Reading at Blackpool earlier this month and he will be a huge addition for them, not only his experience but his quality as well.”
Asked about their summer training sessions, Cahill said: “We were at a stage where we both wanted to keep ticking over so we got together in the summer. While we were debating what we were going to do in our careers, we kept fit and it was good.
“We hired a 4G pitch near where we live and got in a trainer. You can’t replicate games and the sharp stuff you need but we are experienced enough to know what we need for our bodies in terms of fitness and drills. It’s more enjoyable with someone else than on your own so it was fine.”
During eight years at Stamford Bridge, Cahill won the Champions League, the Europa League twice, two Premier League titles, two FA Cups and the League Cup.
The 35-year-old defender has made a flying start to his career at Vitality Stadium, helping Scott Parker’s team win eight and draw one of his nine games, conceding just three goals in the process.
“It’s gone very well,” said Cahill. “More importantly, I’m very pleased with the start for the team. The run we’re on is enjoyable and it’s one we want to keep going and continue for as long as possible. I’ve enjoyed it, it’s been a good start. It’s early days but I’m very pleased.”
Asked whether it had gone better than he had anticipated, Cahill replied: “When you look at the goals conceded, I would say it’s very, very pleasing. It’s something to be proud of collectively as a team and shows we’re doing something right.
“As a defender or goalkeeper, you pride yourself on keeping the ball out of the net so, in that aspect, probably yes.
“In terms of my performances, I said when I first came in, three-and-a-half months without a game was the longest I’d been. Without any pre-season games, I’m delighted to get to the levels I expect of myself. I’m happy with how things are at the moment in terms of fitness so long may it continue.”
Cahill, who was 21 when he last played in the Championship during a loan spell with Sheffield United, went on to become one of the leading appearance-makers in the Premier League, playing 394 games for Aston Villa, Bolton, Chelsea and Palace.
Asked for his thoughts on the Championship, he said: “I didn’t really know what to expect when I first came into this league.
“I’ve played in England all my career so I know about the Championship and every game is very different in terms of formation and how teams play.
“There’s a huge difference with some teams. Some are very direct and others try to play. There’s a real mixture. But it’s always nice to be in a team which is doing well and full of confidence.
“We’ve got some fantastic young and hungry players here and it’s a joy to be a part of that. We’re playing some good stuff and it’s always easier when you’ve got the ball and you aren’t having to get it back.
“It’s relentless and unforgiving trying to win a league, whether it’s the Championship or the Premier League. It’s non-stop. You get a win and enjoy it but then you re-set and quickly go again because it’s unforgiving.
“We’ve just had a nine-point week and that was huge. If you lose three and someone else has a nine-point week, things change so quickly.
“It’s about pushing consistently week in, week out which makes the end result even sweeter if you can get there.
“After the draw at Peterborough, the lads came in and it felt like we had lost. For me, that was a reaction I was buzzing with and that was the reaction I hoped it would be.
“You’re going to have knocks and maybe things don’t go well but it’s about how you react. To go on and win the next game is exactly what you need to do.”
Cahill believes Cherries supporters should be excited by the current crop of players and was asked specifically about Lloyd Kelly, his central defensive partner.
“In terms of ticking boxes to be a top player, he ticks every one,” said Cahill, who won 61 caps for England.
“When I say top player, I don’t just mean go and play in the Premier League at certain clubs, I mean be at the top of the Premier League.
“I think I can pass judgement on that. I’ve played with some good centre-backs who have won many things, both domestically and internationally.
“It’s very early and consistency is what the manager has been trying to drill into the team from the start of the season.
“That’s as a team but, individually, you should be driving to perform consistently at a higher level so that’s what he needs to do.
“When I say ticking boxes, is he quick, aggressive, composed on the ball, can he play out from the back, can he defend? All these things, he ticks the boxes.”
Asked whether he felt Dann and the rest of the Reading defence would have their work out trying to stop Dominic Solanke adding to his 11-goal tally, Cahill replied: “Not many have been able to this season due to the form he’s in.
“He should be so confident going on to the field with 11 goals which are great numbers at this stage of the season.
“Again, it goes back to consistency and trying to drive individuals or mentally driving yourself to get more and more and more.
“I see that mindset with him. He’s going into games just wanting to score goals. His second goal against Huddersfield, he took it fantastically well and his overall play was great.
“He’s lethal at the moment and is the main man. He’s producing the numbers which is great for him and us.”
Cahill scored his first Chelsea goal on his debut in a 4-2 win against Reading in a Premier League clash at Stamford Bridge in August 2012.
He said: “It was a long-range effort and, if I’m totally honest, I think the keeper would have been disappointed with himself. I hit one from outside the box, it skidded off the surface and although he should have done better, I’ll take a 30-yarder!”
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