diff --git a/lib/core/client.js b/lib/core/client.js
index 587c4408121..4eb86c1eff2 100644
--- a/lib/core/client.js
+++ b/lib/core/client.js
@@ -500,7 +500,7 @@ class Parser extends HTTPParser {
     if (shouldKeepAlive && client[kKeepAlive]) {
       const keepAliveTimeout = util.parseKeepAliveTimeout(headers)
 
-      if (Number.isFinite(keepAliveTimeout)) {
+      if (keepAliveTimeout != null) {
         const timeout = Math.min(
           keepAliveTimeout - client[kKeepAliveTimeoutThreshold],
           client[kKeepAliveMaxTimeout]
diff --git a/lib/core/util.js b/lib/core/util.js
index 00348a35080..30ff7f2d13e 100644
--- a/lib/core/util.js
+++ b/lib/core/util.js
@@ -51,8 +51,8 @@ function parseKeepAliveTimeout (headers) {
   for (let n = 0; n < headers.length; n += 2) {
     const key = headers[n + 0]
     if (key.length === 10 && key.toLowerCase() === 'keep-alive') {
-      const m = headers[n + 1].match(/timeout=(\d+)/)
-      return m ? Number(m[1]) * 1000 : undefined
+      const timeout = parseInt(headers[n + 1].split('timeout=', 2)[1])
+      return timeout ? timeout * 1000 : undefined
     }
   }
 }