The 19-year-old was one of the first players to leave the Hammers in their post-relegation fire sale, with Sir Bobby assuming that a bid of £2million would be enough to secure the services of a player with just 15 Premiership appearances to his name.
That was until Roman Abramovich stumped up a fistful of roubles to land Johnson’s signature.
"I love Glen Johnson," he told the Sunday Sun. "I saw him up here in an England Under-21 match and he had a great game.
"I saw Glenn Roeder - who was still West Ham manager at the time - afterwards but he didn't want to sell him.
"But I still said to the chairman in the summer: `Offer £2 million for Johnson - I think West Ham will take it. They've just gone down and they need the money'.
"£2 million for a 19-year-old full-back? I thought they'd take our hand off.
"But two-and-a-half weeks later, he went to Chelsea for £6 million . . . £6 million!"
Johnson has already made enough progress this season to earn a call-up to the senior England squad and, while his defending still needs a lot of work, there is no doubt that he would have been an excellent signing.
He’s certainly a far better player than Stephen Carr.