Tiger Woods made a solid start at the Valspar Championship as Corey Conners grabbed the first-round lead on Thursday.

Woods endured a rollercoaster round in Palm Harbor, Florida, with five birdies and four bogeys.

The 14-time major champion was two under after birdies on holes 10 and 11, but he made back-to-back bogeys on the next two on his way to a one-under 70.

That was enough to leave Woods in a tie for eighth on a congested leaderboard, which is topped by Canadian Conners at four under.

Conners, 26, made a strong start with four birdies on his first eight holes, with only a bogey at the last costing him a bigger lead.

Whee Kim, Kelly Kraft and Nick Watney opened with three-under 68s to be tied for second.

Keegan Bradley, Russell Knox and Jimmy Walker managed 69s to be a shot further back.

Among those joining Woods at one under were Masters champion Sergio Garcia and Adam Scott and English duo Justin Rose and Luke Donald, the 2012 winner.

Rory McIlroy and Jordan Spieth struggled, carding a 74 and 76 respectively.

Northern Irishman McIlroy's first nine holes – the back nine – were solid as he made pars on each, but he struggled from there.

McIlroy bogeyed the second and made a double at five after finding trees off the tee as the four-time major champion ended up back in a tie for 87th.

Former world number one Spieth – the 2015 winner – made five bogeys on the front nine and, while he steadied, it was only enough for a five-over 76.

Defending champion Adam Hadwin made a decent start with an even-par 71.