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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Emma brings you ITV Border's Sunday Weather Forecast.
Clear start, patchy cloud at the east coast, some mist forming further west. Cool in the countryside
Some good sunny spells at first, especially in the west. Much brighter in the east than of late, just some patchy cloud around