A crash in his second run proved costly for Ireland’s Sean Greenwood in the skeleton event at the Sochi Winter Olympics, and Jan Rossiter finished well down the field in the men’s 15km cross-country ski race.
Greenwood had finished Heat 1 in a time of 57.99secs to finish +2.04secs off the pace, before a spectaculas crash in the second heat caused the 26-year-old to record a time of 1min05.11sec and end up +11.11secs off the pace in last place.
Earlier, Canada-based Rossiter finished 82nd in the 15km cross-country event, his time of 48:44.6 was 10 minutes 41.6 seconds behind winner Dario Cologna of Switzerland.
Greenwood began sliding competitively in 2010, initially without a coach, but improved to the point where he won second place overall on the North American circuit last season.
In December he was 17th in the opening world cup race of the season in Calgary, and achieved 19th place in Park City, Utah, and 20th in Lake Placid, New York. In the final world cup race before Sochi, Greenwood secured another top 20 finish.
Since Skeleton returned to the Winter Olympics in 2002 Ireland has had a presence at each competition. Famously Clifton Wrottesley finished a surprise fourth at the Salt Lake City games.
Heats 3 and 4 of the event will take place on Saturday.
In Rossiter's cross-country event, meanwhile, Cologna, who won the skiathlon on Sunday, made a cautious start in the cross-country but was in first place at the 8km mark and his lead never decreased as he went on to became the first skier to win an Olympic 15km race twice in a row.
Swede Johan Olsson won silver and compatriot Daniel Richardsson took the bronze.
In other events, Lizzy Yarnold took Britain’s first gold medal of the games in the women’s skeleton. Yarnold’s final run of 58.09secs gave her a victory margin of 0.97 over silver-medallist Noelle Pikus-Pace of the US. Russia's Elena Nikitina took the bronze medal.
Darya Domracheva stormed to a second gold medal of these games in the women's 15km individual biathlon.
The 27-year-old Belarusian, who claimed the Olympic title in the 10km pursuit on Tuesday, raced round the course in a time of 43 minutes 19.6 seconds to finish 1 min 15.7 secs ahead of Switzerland's Selina Gasparin.
Nadezhda Skardino rounded off the podium positions, crossing the line 1:38.2 behind compatriot Domracheva.
Switzerland's Sandro Viletta saw the competition fall by the wayside as he claimed a surprise gold medal in the super combined.
The 28-year-old had been lying 14th after the downhill stage but conquered a difficult slalom course in a time of 50.32 seconds to set his rivals a target of two minutes 45.20 secs.
Bode Miller and Aksel Lund Svindal failed to pass the figure, while Kjetil Jansrud, the leader after the downhill stage, also came up short to leave Viletta celebrating at the finish line.
Pre-race favourite Ted Ligety of the United States could only manage a 12th-placed finish.