Sam Bothwell is a young man on the rise following another sparkling performance at the ITF under-18 event at Donnybrook yesterday.
Bothwell, whose 17-year-old brother Peter is up to 521 in the world, came through a rollercoaster clash with Great Britain's Luke Simeone, winning 6-4 6-4.
The victory means he is the last Irishman standing in Dublin as he now faces number one seed Ben Stride, who defeated Joe Mullen 6-3 6-0.
Bothwell, 15, broke early in both sets before being broken and finding himself trailing only to rally and produce his best tennis to snatch each set.
Coming into the tournament, Bothwell was searching for his first ITF points having been as high as 111 in the European Tennis Association rankings at under-14 but now he can expect his under-18 ranking to drop significantly.
Bothwell said: "I knew what to expect from Luke because I had seen him before. He likes to grind you down but I had my gameplan and it paid off in the end.
"I was keen to keep many of the rallies short because the longer it went the more it would suit his game.
"I probably played my best tennis in the previous round but I'm very happy with how I played and to be in the semi-finals is great.
"I just have to stay focused now and get ready for a tough match against the number one Ben Stride.
"The whole tournament has given me a lot of experience ahead of the ITF in Belfast next week, that's going to be great, being able to play on home turf."
In the girls event, Karola Bejenaru continued her stroll through the opposition when she defeated Dundalk's Ruth Copas 6-0 6-1 – a repeat of their Ulster Open final meeting last month.
Bejenaru is playing some of her best ever tennis, just in time for the Windsor girl playing on her home court in the Belfast City event next week.
The 16-year-old, sponsored by Dominos, produced a series of winners at Donnybrook yesterday on her way to setting up a semi-final clash with Emily Appleton of Great Britain, who defeated Israel's number four seed May Kimhi 6-2 6-1.
Young Dubliner Jennifer Timotin saw her fine run come to an end when she went out to number three seed Ceire Mullins 6-4 7-5.
Bejenaru's coach Przemek Stec is naturally very pleased with her progress and hopes she can now go all the way.
Stec said: "Karola has shown over recent tournaments that she is now expected to make semis and finals at this level and hopefully she can go and win this ahead of the Windsor event."
Meanwhile, Anne Keothavong is confident she is leaving British women's tennis in a healthy state after announcing her retirement yesterday.
The 29-year-old, who reached a career-high ranking of 48 four years ago, is joining BT Sport as part of their team to cover the WTA Tour. Keothavong said: "I have given my decision a lot of thought and I believe this is the right time to move on to the next stage of my career.
"I think I am leaving tennis in excellent shape with both Laura Robson and Heather Watson leading the way for Britain in the women's game.
"I am now focusing on my exciting new challenge with BT Sport, where I hope I can provide insight and analysis for tennis fans."