Scottish Cup preview: What to watch in fourth round as top-flight sides enter

Shock results are the order of the day when the Scottish Cup fourth round rolls into view - and this weekend's set of fixtures has the potential to serve up a feast of surprises.

Hearts - live on BBC Scotland on Saturday lunchtime - face a tricky tie at The Spartans while Celtic and Rangers both have games against teams several rungs down the ladder with dreams of giant-killing.

There are also plenty of other tasty stories to whet the appetite across the weekend, and here are just a few of them...

When's a shock not a shock?

Second-tier title hopefuls Raith Rovers will fancy their chances at Livingston, who are anchored to the bottom of the Premiership and on a miserable 13-game winless run.

Despite suffering back-to-back Championship defeats in their last two outings, Ian Murray's Rovers are still challenging at the top of the table as they sit level on points with leaders Dundee United.

As for Livingston, it has been a miserable campaign as their six-year Premiership status is in jeopardy, with David Martindale's side six points adrift at the foot of the table.

Eleven defeats in their last 13 games, plus a serious lack of goals, sent the West Lothian club into the winter break battered and bruised. But a victory over Saturday's opponents, who they have beaten twice in the Scottish Cup in the last four seasons, could ignite their campaign.

Celtic on the Buckie, Rangers on the Rock

Rangers and Celtic get their Scottish Cup campaigns under way in front of the TV cameras with two significantly smaller clubs as opposition.

The holders will begin their cup defence by playing host to Highland League challengers Buckie Thistle while Rangers make the short trip to Dumbarton on Saturday night.

Buckie boast the high-profile support of horror legend Stephen King, who namechecked them in his bestselling book If It Bleeds, and has been a vocal supporter of the side on social media. Can the Moray side consign Celtic to a nightmare on Sunday lunchtime?

Meanwhile, Dumbarton reached the fourth round the hard way, coming back from 2-0 down against Banks O'Dee to snatch victory with goals in the 97th and 102nd minutes - then followed that up with a chaotic 5-4 extra-time win against Annan.

Revenge bid and an Edinburgh derby

Partick Thistle travel north to face Ross County with revenge in mind. The sides meet again for the first time since last season's epic play-off final, which saw County retain their Premiership status on penalties after a remarkable Thistle collapse.

It will add more than a pinch of spice to their cup meeting, with Thistle challenging for the Championship and County having won just two of their last nine matches.

St Johnstone - another bottom-half Premiership side - had a miserable League Cup group campaign at the start of this season and are also tasked with safely negotiating a tricky tie at in-form Airdrieonians.

Saturday lunchtime's big kick-off offers SPFL new boys The Spartans the chance to build on their Scottish Cup reputation over their high-flying city rivals Hearts.

There are only a couple of miles between the two clubs in distance but while they have faced each other in friendlies, this will mark a rare competitive clash - in front of the BBC Scotland cameras - between the Edinburgh sides.

In previous years Spartans have enjoyed a host of cup upsets, claiming the scalps of Arbroath and Queen's Park when a non-league side.

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