Extract Substring from Nagios Check Result

I am working with the results from check_http in Nagios. Grafana is showing the mean of that result (HTTP OK: HTTP/1.1 301 Moved Permanently - 515 bytes in 0.018 second response time |time=0.018080s;;;0.000000 size=515B;;;0) as 259.2 (which is the average of 515 and 0).

I’ve tried creating a variable with a regex of .+HTTP/1.1\s(\d{3})\s.+ , but that doesn’t seem to be getting me anywhere.

I also tried REGEXP_SUBSTR while editing the sql string in plaintext, that didn’t work either.

All the guides I’ve seen on regexes are focused on templating host and service names. I’m focused on modifying the “value” field.