Meanings of defensive linchpin in English

In Virgil van Dijk, Liverpool have the multi-faceted defensive linchpin they have been craving.

For many, many moons Ireland's success revolved around the driving force, the defensive linchpin, of a man who wore number 13.

It was during this early part of his career that the English-born Williams started on his journey to becoming Wales's defensive linchpin.

The manager, who had wanted to strengthen in Laporte's position before the start of the season, described the loss of his defensive linchpin as hard.