Extracting an IP address from a particular string in Lua

I want to extract a particular value from a string . This is my string

iptables -t nat -A PREROUTING -p tcp -m tcp --dport 666 -j DNAT --to-destination 192.168.19.55

How can i extract 192.168.19.55 ip address from this string using string.match in lua ?

I done with local ip = s:match("--to-destination (%d+.%d+.%d+.%d+)")) but i didn't get the value 192.168.19.55 . I am getting empty value .

Any mistake in this ? Any suggestions ?