diff --git a/src/lib/tabs/ink-bar.ts b/src/lib/tabs/ink-bar.ts
index 4e3c677d8496..0dff8ce6a3c8 100644
--- a/src/lib/tabs/ink-bar.ts
+++ b/src/lib/tabs/ink-bar.ts
@@ -59,6 +59,6 @@ export class MatInkBar {
     const inkBar: HTMLElement = this._elementRef.nativeElement;
 
     inkBar.style.left = element ? (element.offsetLeft || 0) + 'px' : '0';
-    inkBar.style.top = element ? (element.offsetWidth || 0) + 'px' : '0';
+    inkBar.style.width = element ? (element.offsetWidth || 0) + 'px' : '0';
   }
 }