Root the Younger scored 110 not out – reaching his century with a leg-side clip for two off Joe’s bowling – as Glamorgan declared on 241-4 in their second innings one hour into the final day, leaving Yorkshire 379 to win from a minimum of 76 overs.
It followed a fine 43 by the 28-year-old left-hander – the junior Root by around 19 months – in the visitors’ first innings total of 330.
In contrast, Root senior managed 16 in Yorkshire’s first innings reply of 193, the England Test captain falling in the most uncharacteristic style when he sliced a full toss from off-spinner Callum Taylor high to mid-off.
Root the Elder fared no better yesterday, perishing for 13 when he edged medium-fast bowler Dan Douthwaite low to first slip as he tried to defend.
Yorkshire were 47-3 at that stage with the best part of 60 overs left in the game. Things could have got tricky as they sought to stave off a club that has only once won a County Championship match at this ground – in 1999, when the great South African all-rounder Jacques Kallis, then of Glamorgan, made the last of his 22 Championship appearances.
But Lyth, who batted like a man fine-tuned by the flat pitches of August rather than one feeling his way through the challenging conditions of April, ensured that Yorkshire avoided an inglorious start to their title quest, scoring an unbeaten 115 and sharing in a fourth-wicket stand of 131 inside 31 overs with Harry Brook (60) before Yorkshire reached 223-4 by the time that hands were shaken at 5.15pm.
Lyth, who faced 196 balls and hit 14 fours and two sixes in an innings full of flowing strokes, decisive footwork and bristling intent, had a fine match after also top-scoring with 52 in the first innings.
“Personally it’s been a fantastic game for me,” he said. “I was disappointed first innnings not to go on, but the way that I’ve played in the friendlies and now in this game... I’m absolutely thrilled.”
Reflecting on his quarter-century of first-class hundreds, 24 of which have come for Yorkshire and the other in the 2015 Headingley Test against New Zealand, Lyth said: “It’s a nice milestone, but I feel like I can score a hell of a lot more (hundreds) and I should have a hell of a lot more.
“What I want to do is be more ruthless when I get in and make big scores. Over the last couple of seasons I haven’t done that as much as I’d like, so it’s a fantastic start for me and hopefully I can kick on.”
Chief interest at the start of day four focused on whether Billy Root could reach a sixth first-class century on his 34th appearance, his second outing against his native county, having played against Yorkshire for Leeds-Bradford MCCU in 2015.
In watery sunshine and bitterly cold weather, with the temperature once more in the low single figures, Root leg-glanced the opening ball of the day from Brook to the fine-leg boundary after resuming on 77.
Cooke, who had 57 overnight, hit Dom Bess for a straight six towards the Carnegie Pavilion as the fifth-wicket pair continued impressively.
Root the Younger then milked his brother to reach a 210-ball century – Root the Elder applauding graciously and then fist-bumping his sibling at the end of the over and patting him on the back several times.
“Oi, that’s quite enough of that carry on,” one could almost hear Arthur ‘Ticker’ Mitchell and Brian Sellers chastising as they looked down from heaven, two Yorkshiremen who did not go in for displays of affection.
When Glamorgan declared, Root had hit nine fours and two sixes in a 217-ball innings and Cooke eight fours and one six in a 213-ball stay, their stand worth 212 inside 70 overs.
Coad was Yorkshire’s most successful bowler with 3-18 from seven overs before the pectoral injury that curtailed his involvement, new-ball partner Matthew Fisher (abdominal) also going down during the match with both men out of this week’s trip to Kent as Yorkshire await further news on their lay-off times.
In better news, Gary Ballance will return in Canterbury after the concussion injury that ruled him out of this game, with the Kent match – along with the eight other Championship fixtures being played next week – to pause between 2.50 and 4.10 on Saturday afternoon (day three) to coincide with the funeral of the Duke of Edinburgh.
Bess went wicket-less here with match figures of 34.4-106-0 – although this was hardly weather for spinners, with another two overs lost to a snow flurry yesterday following the mini-blizzard that accounted for two-thirds of day three and cost Glamorgan the chance to put Yorkshire under more severe pressure.
As it was, the hosts never looked in danger after Root was out, Lyth and Brook playing with growing freedom before Brook fell to the tenth ball after tea when he punched Michael Hogan to Root the Younger at cover. Lyth and Jonny Tattersall then shared an unbroken 45.
Earlier, Tom Kohler-Cadmore was adjudged caught behind playing forward to Timm van der Gugten and Tom Loten ruled lbw to Hogan to a ball that seemed to strike him outside the line.
It could have proved costly had Root’s departure triggered a clatter, but Lyth and Brook soon led the hosts into tranquil territory as Glamorgan’s brave charge petered out like the snows for which this game will be remembered.