Why does my dog attack me when the rugby is on?

Couple of possibilities, and the answer probably depends on what "attacks" actually looks like — is it bitey-play-mode (zoomies, mouthing, jumping up) or genuinely escalated (stiff body, growling, drawing blood)?

The most common version of this is that your dog isn't reacting to the rugby — it's reacting to you reacting to the rugby. From a dog's point of view, you've gone from baseline-relaxed-human to leaning forward, tensing up, shouting at the screen, throwing your arms around. That's an enormous behavioural shift, and the two things a dog can interpret it as are (a) something is wrong and we are under threat, or (b) we are now playing a wild new game. Either way the dog joins in.

There's also a smaller chance the TV itself is the trigger — modern screen refresh rates are high enough that dogs can track motion on them, and a pack of figures sprinting around in a tight group can set off prey drive in certain breeds.

What does the "attack" actually look like, and what kind of dog is it?

Ah, that changes the picture quite a bit — shih-tzus aren't really a prey-drive breed and if you're sat still, the "I'm matching your energy" theory doesn't hold. So scratch that one.

For a small companion breed who's calmly co-existing with you all week and only loses it during the rugby, the more likely culprit is attention competition. Shih-tzus were specifically bred to be on humans — your focus is their currency. Six days a week you're presumably looking at, talking to, or just generally available to him. Then for 80 minutes a screen takes all of that focus away, and he can't compete with it. Biting your hand or arm is the most reliable way to get you to look at him again, even briefly. If you ever respond to it — even to push him off, say his name, or move him — you've taught him the move works.

The give-away question: does he do this if you're reading a book for 80 minutes, or doing something on your laptop? Or is it specifically when you're locked into the TV?

And — what does the attack itself actually look like? Lunging and nipping at hands? Going for ankles? Latching on?

Okay that's a really useful narrowing — that's actually quite diagnostic.

If you're sat still and TV shows don't bother him, then the rugby itself has to contain a signal that other TV doesn't. The two strong candidates:

1. The whistle. Refs' whistles are at a pitch and intensity that dogs find genuinely aversive — much more salient to him than to you. Sharp, sustained, and they come in unpredictable bursts. Lots of dogs hate them; some respond by trying to make the source stop, which can include lunging at the nearest associated thing.
2. The crowd noise. A stadium crowd has a low rumbling baseline that suddenly swells into a unified roar on tries and big tackles. That's quite similar to the sound profile of a large group of distressed or aggressive animals. Most TV shows don't carry that texture.

Easy way to A/B test which one: watch a match on mute with subtitles for the commentary. If he's fine, it's the audio (and you can narrow further — try it with just commentary audio and no crowd/whistle sounds, e.g. a radio call layered over the silent video). If he still goes for you with the sound off, it's something visual or it's the situation itself (you sat in That Spot doing That Thing once a week).

A couple of other questions while we're triangulating:

• Does he only do it during live rugby, or also recorded? (If only live, anxiety from your own anticipation might be a factor even if you don't feel animated.)
• And — you still haven't told me what the attack actually looks like. Nipping at your hands? Going for ankles? Latching on and not letting go?

Right, so this is mostly attention, with the rugby acting as the trigger because it's the one stretch of the week you're genuinely unavailable. He can probably tell the difference between you half-watching a show with your phone in your hand and you being fully locked into 80 minutes of something you've waited all week for. That latter state, to him, is uncharacteristic and intolerable.

Foot attacks and jumping up is also a pretty unambiguous shih-tzu signal — it's not aggression, it's "let me up there." He doesn't actually want you to stop watching, he wants to be on you while you do it.

The fix is therefore boring but probably effective: let him be on the sofa with you during the match. Lap, or a blanket folded up next to you so he can curl in against your leg. A lot of small companion breeds simply cannot tolerate physical separation from their person during a sustained "absent" state — your attention can go elsewhere as long as the contact is maintained.

Two operational notes:

• Don't invite him up while he's attacking your feet — wait for a lull, then call him up. Otherwise the path "bite Dad's feet → get on lap" gets cemented and he'll start the match with foot attacks every time as the opening move.
• If he doesn't settle even when on the sofa, then it's worth adding a long-lasting chew (something like a frozen Kong or a yak chew) for him to work on while leaning against you.

Does he normally try to get on your lap on the sofa, or is he more a floor-and-bed dog?

Okay so the lap-dog theory falls down — if he's not seeking contact normally, he's not suddenly going to want it during the match either.

Updated read: this is probably arousal displacement. He's hearing the audio of the match (which is genuinely a strange acoustic event compared to your normal day), he's getting wound up by it, and a small dog with no way to discharge that arousal will reliably go and bite the nearest available moving thing — which is your feet. The fact that he's going for feet specifically rather than hands or face is the tell. Feet move slightly even when you think you're sitting still — small shifts, unconscious foot-taps during tense moments — and small breeds lock onto that motion like it's prey.

Three things to try, in order of how much yield they're likely to give:

1. Long-lasting chew at the start of the match. Yak chew, bully stick, frozen Kong with something he likes. The point is to give his jaw and his arousal somewhere to go before he goes looking himself. This single move solves it for most people.
2. Designated rugby spot. A specific mat or bed in the room, ideally within his eyeline of you but not under your feet. Take him to it at the start, give him the chew there. Same place every week. Dogs love a ritual.
3. Drop the TV volume by ~20% during rugby specifically. You won't really notice, but you'll cut the whistle peaks down to a less uncomfortable level for him, and that might be doing more of the work than you'd expect.

And — if he does come and attack your feet anyway, the worst thing to do is react. No pushing him off, no "off," no eye contact. If it's bad, calmly stand up and walk out of the room for 30 seconds. Boring is the goal.

Try that for two or three matches and see where you land. My guess is the chew alone resolves 80% of it.