diff --git a/x-pack/plugins/observability/public/pages/overview/components/sections/metrics/metric_with_sparkline.tsx b/x-pack/plugins/observability/public/pages/overview/components/sections/metrics/metric_with_sparkline.tsx
index 3e4b0476b5075..bd292a2bf88cb 100644
--- a/x-pack/plugins/observability/public/pages/overview/components/sections/metrics/metric_with_sparkline.tsx
+++ b/x-pack/plugins/observability/public/pages/overview/components/sections/metrics/metric_with_sparkline.tsx
@@ -36,7 +36,7 @@ export function MetricWithSparkline({ id, formatter, value, timeseries, color }:
   const theme = [EUI_SPARKLINE_THEME_PARTIAL];
   const baseTheme = isDarkTheme ? DARK_THEME : LIGHT_THEME;
 
-  const colors = theme[1].colors?.vizColors ?? [];
+  const colors = baseTheme.colors?.vizColors ?? [];
 
   if (!value) {
     return (