Castle fronted Sky's coverage of the end-of-term dollarfest, a job that would have been comfortably anonymous had it not been for Henman's late promotion from bench-warmer to wallet-filler. Then Oxford's finest marmalised Michael Stich and in no time Castle was in unknown territory: lots of people were watching him.
He must have got behind with his offerings to the television gods, however, for no sooner had he drawn breath to pronounce: "Tim Henman taking on the Wimbledon finalist Mal Washington - that match coming at you right after the break", than it became clear that all that was coming at us was more of Castle and his studio guest, Peter Fleming.
Henman and Washington were indeed due on court, but Sky had underestimated the appetites of German tennis fans. Boris Becker had just dismissed Jakob Hlasek, and the good burghers of Munich were tucking in to the good burgers of Munich, laying waste to the wurst and taking time over their stein. Tennis could wait.
Which meant that the viewers had to, while Castle and Fleming shot the breeze. "We're looking forward to Tim Henman and Mal Washington," Castle noted, adding before the next commercial break, "We are awaiting the players out on court, we hope they'll be there when we return . . ." They weren't.
"Some kind of a hitch over in Munich," Castle announced with just a hint of desperation. "We expect those players to come out on court fairly soon - hope they do." In between such bulletins, the blond, craggy pair discussed Henman's volley, service, build, personality, upcoming T-shirt range and racket endorsement deal. It was a bit like eavesdropping on two total strangers at a party who have found that they have but one obscure interest in common.
To be fair to Castle, he was pretty unflustered by the delay, betraying no evidence of panic in conversation or body language. He may not have been much cop with forehand or backhand, but he's a dab hand at "...on the other hand". The true test for Castle, though, will be when there is a glitch in the golf or basketball coverage that he presents. How handy will he be with the waffle iron or the free throwaway remark?
Profoundly strange behaviour on Lumberjacks OK!, Channel 4's late-night focus on "lumberjack sports", which in the heavy weirdness department makes The X-Files look like Blue Peter. This week we travelled to Squamash, a British Columbian town named after a female native American steamroller accident victim.
The star of the show was David Jewett, an axe-sports specialist with disconcerting eyes. For the uninitiated - around 99.99 per cent of you, at a guess - axe sportspersons stand on logs and chop through them, or stand next to them and chop through them. When they want a break, they swap to six-foot saws, and the final of the event involves lobbing a large axe at a roundelled target. Imagine darts directed by Sam Peckinpah, and you're in the picture.
"I just always had this gut feeling that I was going to find a sport that I was going to excel in," Jewett revealed. "All of a sudden I ran across this sport of wood-chopping." Kind of thing you do run across in Squamash, usually when trying to avoid running across squaws.
"When I come off that block," Jewett continued with a stare, "and I've won the heat or the event, all of a sudden there is a reward and it's all coming to you right now. That's a good facial expression, usually." You can imagine Dave at home in front of the mirror, practising them: pleased, elated, joyful.
But there are darker days in the wood-chopper's life. "There's lot of times it's just agony when you come off and you're the last person in your heat and you realise that you just drove a thousand miles to get your tail kicked." A clip of Jewett in defeat ran at this point. After a final despairing blow at a stubborn stump, he strode out of the arena, sheathing his blade with an eloquent "f***".
It's irresistible to imagine a touchline reporter - Sky's Nick Collins, for example - at the Lumberjack games. Jewett has just finished last again, and wrenches his mighty axe out of the unsevered log as Collins approaches, microphone in hand. "Well, Dave, you met your match this time. How do you feel?" Thunk. End of interview. End of interviewer. Luckily, in real life Jewett has an outlet for his feelings. "My mother", he explained, "is a social worker."