My last dog did the same thing, maybe an average of 10 minutes. We just ended up keeping unstuffed toys for her to play with. The newest dog is still learning how to play (greyhound that's fresh off the track, never seen toys or 'played' before). She actually hasn't torn any of her toys apart yet although she does break all the squeaky things inside them.

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EVO IX - just a really expensive boost gauge and a K&N air filter
96 Eclipse RS -awaiting registration and inspection
95 Eclipse GS - parts car
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