Rory Best believes Ireland have "too many good players" not to be successful in this year's Six Nations tournament.

Ireland opened their campaign with home victories over Scotland and Wales as they bid for a fourth Grand Slam.

Best, who captained Ireland to Grand Slam success in 2018, says he has been impressed with how the side have started under head coach Andy Farrell.

"I think they have been really good," said Best, who retired from Ireland duty after the 2019 World Cup.

Having not played since their World Cup quarter-final exit at the hands of New Zealand in October, Ireland opened their Six Nations campaign with a 19-12 victory over Scotland before ending Wales' hopes of consecutive Grand Slams with a 24-14 win in Dublin.

But Best, who won 124 caps during his 15-year Ireland career, says he is not surprised by how they have started the tournament.

"I actually thought Ireland were going to have a good Six Nations," he said.

"There are too many good players pulling on that green jersey for Ireland not to be successful.

"It's a really strong start and hopefully they can continue that into Twickenham, which is a really difficult place to go.

"England are under a little bit of pressure but at the end of the day they're World Cup finalists so they're going to be incredibly tough but that's not to say Ireland can't do it."

'He's made a strong start' - Best on Herring

Best added that he is also pleased with how well Rob Herring, one of his former Ulster teammates, has taken to life as Ireland's first-choice hooker given the stiff competition for a starting spot in Farrell's team.

Herring, 29, has edged out highly rated Leinster youngster Ronan Kelleher to start in the front row against Scotland and Wales having never represented Ireland at the Six Nations before this year.

"He's playing really well," said Best.

"Rob's a great player and I think from an Ulster point of view, it was nice that whenever I gave the shirt up it was an Ulster player who came in and took it.

"It's good to have that Ulster continuity, but also from his point of view, he's had a really strong start in that Irish pack and long may that continue."