Eckhoff set off eighth with ground to make up on World Cup leader Dorothea Wierer who won the sprint on Friday.
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However Wierer struggled with her early shooting, missing two in her first shoot and then one in each of the next three.
Highlights: Boe digs deep to take relay for Norway
15/12/2019 AT 15:07
That opened the door for the rest of the chasing pack and Eckhoff took advantage alongside compatriot and close friend Ingrid Landmark Tandrevold, who didn’t miss a shot in her first two.
Whilst Eckhoff continued to press home her advantage Tandrevold fell away and although she secured third she was passed by Swedish number one Hanna Oeberg.
“I am very happy today; it was my first 20! I was really emotional when I made it, so I could not have been happier." Eckhoff said afterwards.
"And especially when Ingrid, we were standing there together; it was amazing!”

Highlights: Eckhoff wins perfect Pursuit

France’s Justine Braisaz chased Tandrevold hard but in the end had to settle for fourth.
Wierer finished tenth to cap off a disappointing day for the Italians, who saw Lisa Vittozzi have another difficult day as she finished 25th.
Eckhoff’s impressive victory, only one other woman shot perfectly, rounds off a strong weekend for Norway after they also took victory in the women’s pursuit and have seen Johannes Thingnes Boe in dominant form on the men’s side.
And it was Boe who shone during the men's pursuit.
Coming into the final leg he had well over half a minute to make up on the German team but he reined in Benedikt Doll with a ridiculous display of skiing.
Boe shot rapidly in the final section but missed a couple, but his pace meant that the gap between him and Doll, who also missed two, was down to 13.8s going into the final stretch.

'Can you believe that?!' - Boe produces extraordinary comeback for Norway

There was still work to be done and Boe put it in, clawing his way past Doll, who fought hard, and finally going into the lead on the final stretch.
It was Boe's third victory of the weekend in Austria.

Highlights: Boe digs deep to take relay for Norway

'Can you believe that?!' - Boe produces extraordinary comeback for Norway
15/12/2019 AT 15:03
Highlights: Boe takes victory in Pursuit
14/12/2019 AT 16:40