Shrewsbury goalkeeper Chris Weale fouled JP McGovern in the area on 68 minutes and Miller put United back on terms.
The game ended 2-2 but there was worse news for Carlisle with winger Matty Robson limping out of the game after only nine minutes with a suspected back problem
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A look ahead at the Bank Holiday forecast for the Border region.
Cumbria County Council will start work on a £320,000 resurfacing scheme on 6 June, between 6.00pm and 12.30am.
ITV Border's favourite Tapir has left the Lake District Wildlife Park near Keswick, to travel to his new home in the United Arab Emirates.