In the early hours the government won its vote on the behemoth-like task of transferring laws incorporated from the EU on to a new statute book.
In the end Labour doubts and a strict hand from the Tory whips won the day and the numbers were more comfortable than the squeaky feeling at the start of the political week suggested.
Tories with unease about the withdrawal bill have already drawn up proposed amendments, changes to the bill and here's the rub - they say they already have at least a dozen colleagues signed up, including four influential chairs of Westminster committees.
Why does that matter? Remember, the government's majority (with the DUP) is so slim only six grumpy Tories can sink a bill.
So a dirty dozen, as ministers might see them, can force them to change their position or lose.