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BOSTON MARATHON 2025

Nat Blaesser

Bib: 7710•M

VA

0:00
0:00
/ mi
Masters
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Overall
#0 / 28404
Top 16%
Gender (Male)
#0 / 16105
Top 26%
Masters (Masters Men)
#0 / 10463
Top 12%
Division (M40-44)
#0 / 2247
Top 31%
Race Day Weather
50°/40°F
broken clouds

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
21:12
Rank: #6499
Start → 5K
21:12 | 6:49/mi
10K· 6.21 mi
42:12
Rank: #6222 (+277)
5K → 10K
21:00 | 6:46/mi
15K· 9.32 mi
1:03:03
Rank: #5867 (+355)
10K → 15K
20:51 | 6:43/mi
20K· 12.43 mi
1:24:06
Rank: #5648 (+219)
15K → 20K
21:03 | 6:47/mi
Half· 13.11 mi
1:28:39
Rank: #5602 (+46)
20K → Half
4:33 | 6:40/mi
25K· 15.53 mi
1:44:59
Rank: #5349 (+253)
Half → 25K
16:20 | 6:44/mi
30K· 18.64 mi
2:06:13
Rank: #4925 (+424)
25K → 30K
21:14 | 6:50/mi
20M
2:15:38
Rank: #4793 (+132)
30K → 20M
9:25 | 6:56/mi
21M
2:22:52
Rank: #4636 (+157)
20M → 21M
7:14 | 7:14/mi
35K· 21.75 mi
2:28:07
Rank: #4646 (-10)
21M → 35K
5:15 | 7:01/mi
23M
2:36:58
Rank: #4581 (+65)
35K → 23M
8:51 | 7:04/mi
24M
2:43:59
Rank: #4564 (+17)
23M → 24M
7:01 | 7:01/mi
40K· 24.85 mi
2:50:07
Rank: #4576 (-12)
24M → 40K
6:08 | 7:10/mi
25.2M
2:52:46
Rank: #4575 (+1)
40K → 25.2M
2:39 | 7:41/mi
Finish· 26.22 mi
2:59:30
Rank: #4532 (+43)
25.2M → Finish
6:44 | 6:36/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:28:39
Pace6:46 /mi
2nd Half
Distance13.11 mi
Time1:30:51
Pace6:56 /mi
📊Positive Split: 2.5% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:29:1021:126:4921:12
6:49
-
10K
6.21 mi10:50:1042:126:4721:00
6:46
-0:03
15K
9.32 mi11:11:011:03:036:4620:51
6:43
-0:03
20K
12.43 mi11:32:041:24:066:4621:03
6:47
+0:04
Half
13.11 mi11:36:371:28:396:464:33
6:40
-0:07
25K
15.53 mi11:52:571:44:596:4516:20
6:44
+0:04
30K
18.64 mi12:14:112:06:136:4621:14
6:50
+0:06
20M
20.00 mi12:23:362:15:386:479:25
6:56
+0:06
21M
21.00 mi12:30:502:22:526:487:14
7:14
+0:18
35K
21.75 mi12:36:052:28:076:495:15
7:01
-0:13
23M
23.00 mi12:44:562:36:586:498:51
7:04
+0:03
24M
24.00 mi12:51:572:43:596:507:01
7:01
-0:03
40K
24.85 mi12:58:052:50:076:516:08
7:10
+0:09
25.2M
25.20 mi13:00:442:52:466:512:39
7:41
+0:31
Finish
26.22 mi13:07:282:59:306:516:44
6:36
-1:05

Checkpoints & Pacing

📈Pace Line

Pace Progression

Track your pace changes throughout the race. Dot colors mark your quickest to easiest segments, relative to your own pace.

Fastest Pace

6:36 /mi

Average Pace

6:51 /mi

Slowest Pace

7:41 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:56:51

99% of race

Time at Steady Pace

2:39

1% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 6:51 /mi

Loading chart...
Faster pace (< avg)
Steady pace (≈ avg)
Slower pace (> avg)

🎨Heatmap

Pace Heatmap

Where you sped up and eased off relative to your own pace across the race. Colors are relative to your own range, not to other runners.

Loading...
0mi6.6mi13.1mi19.7mi26.2mi
Pace:
Faster
Steady
Slower

Click or hover over segments to see details

✨Sparklines

Checkpoint Splits with Pace Trends

Overall Pace Trend

CheckpointDistanceTime of DayTimeAvg PaceSegmentPaceTrendRank
5K
3.11 mi10:29:1021:126:4921:12
6:49
#6499
10K
6.21 mi10:50:1042:126:4721:00
6:46
#6222
15K
9.32 mi11:11:011:03:036:4620:51
6:43
#5867
20K
12.43 mi11:32:041:24:066:4621:03
6:47
#5648
Half
13.11 mi11:36:371:28:396:464:33
6:40
#5602
25K
15.53 mi11:52:571:44:596:4516:20
6:44
#5349
30K
18.64 mi12:14:112:06:136:4621:14
6:50
#4925
20M
20.00 mi12:23:362:15:386:479:25
6:56
#4793
21M
21.00 mi12:30:502:22:526:487:14
7:14
#4636
35K
21.75 mi12:36:052:28:076:495:15
7:01
#4646
23M
23.00 mi12:44:562:36:586:498:51
7:04
#4581
24M
24.00 mi12:51:572:43:596:507:01
7:01
#4564
40K
24.85 mi12:58:052:50:076:516:08
7:10
#4576
25.2M
25.20 mi13:00:442:52:466:512:39
7:41
#4575
Finish
26.22 mi13:07:282:59:306:516:44
6:36
#4532
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM40-44Seg. OverallSeg. MalesSeg. M40-44
5K3.11 mi3.11 mi6499591659165188(Top 18%)4801(Top 30%)4801(Top 214%)
10K6.21 mi3.10 mi6222+2775698+2185698+2185955(Top 21%)5449(Top 34%)5449(Top 243%)
15K9.32 mi3.11 mi5867+3555385+3135385+3135188(Top 18%)4801(Top 30%)4801(Top 214%)
20K12.43 mi3.11 mi5648+2195188+1975188+1975069(Top 18%)4677(Top 29%)4677(Top 208%)
Half13.11 mi0.68 mi5602+465149+395149+395036(Top 18%)4665(Top 29%)4665(Top 208%)
25K15.53 mi2.42 mi5349+2534928+2214928+2214395(Top 15%)4073(Top 25%)4073(Top 181%)
30K18.64 mi3.11 mi4925+4244554+3744554+3743667(Top 13%)3397(Top 21%)3397(Top 151%)
20M20.00 mi1.36 mi4793+1324439+1154439+1153710(Top 13%)3416(Top 21%)3416(Top 152%)
21M21.00 mi1.00 mi4636+1574299+1404299+1403311(Top 12%)3049(Top 19%)3049(Top 136%)
35K21.75 mi0.75 mi4646-104295+44295+45463(Top 19%)4703(Top 29%)4703(Top 209%)
23M23.00 mi1.25 mi4581+654225+704225+704174(Top 15%)3718(Top 23%)3718(Top 165%)
24M24.00 mi1.00 mi4564+174203+224203+224729(Top 17%)4069(Top 25%)4069(Top 181%)
40K24.85 mi0.85 mi4576-124205-24205-24909(Top 17%)4153(Top 26%)4153(Top 185%)
25.2M25.20 mi0.35 mi4575+14200+54200+54279(Top 15%)3635(Top 23%)3635(Top 162%)
Finish26.22 mi1.02 mi4532+434156+444156+443391(Top 12%)2975(Top 18%)2975(Top 132%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 18%
×21stories
+97ft-345ft

Overall

5188

Males

4801

M40-44

4801

5K→10K

3.1 - 6.2 mi

Top 21%
×5stories
+79ft-138ft

Overall

5955

Males

5449

M40-44

5449

10K→15K

6.2 - 9.3 mi

Top 18%
×3stories
+67ft-78ft

Overall

5188

Males

4801

M40-44

4801

15K→20K

9.3 - 12.4 mi

Top 18%
×5stories
+106ft-86ft

Overall

5069

Males

4677

M40-44

4677

20K→Half

12.4 - 13.1 mi

Top 18%
×2stories
+19ft-37ft

Overall

5036

Males

4665

M40-44

4665

Half→25K

13.1 - 15.5 mi

Top 15%
×4stories
+66ft-88ft

Overall

4395

Males

4073

M40-44

4073

25K→30K

15.5 - 18.6 mi

Top 13%
×9stories
+181ft-148ft

Overall

3667

Males

3397

M40-44

3397

30K→20M

18.6 - 20.0 mi

Top 13%
×5stories
+64ft-50ft

Overall

3710

Males

3416

M40-44

3416

20M→21M

20.0 - 21.0 mi

Top 12%
×8stories
+106ft-24ft

Overall

3311

Males

3049

M40-44

3049

21M→35K

21.0 - 21.8 mi

Top 19%
×7stories
+17ft-86ft

Overall

5463

Males

4703

M40-44

4703

35K→23M

21.8 - 23.0 mi

Top 15%
×5stories
+23ft-63ft

Overall

4174

Males

3718

M40-44

3718

23M→24M

23.0 - 24.0 mi

Top 17%
×6stories
+12ft-82ft

Overall

4729

Males

4069

M40-44

4069

24M→40K

24.0 - 24.9 mi

Top 17%
×1story
+6ft-20ft

Overall

4909

Males

4153

M40-44

4153

40K→25.2M

24.9 - 25.2 mi

Top 15%
×1story
+13ft-16ft

Overall

4279

Males

3635

M40-44

3635

25.2M→Finish

25.2 - 26.2 mi

Top 12%
×2stories
+22ft-21ft

Overall

3391

Males

2975

M40-44

2975

Passing Analysis

Category:
Athletes Passed
2414
Passed By
447
Net Change
+1967
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#6499
5K → 10K35881+277#6499#6222
10K → 15K37722+355#6222#5867
15K → 20K25233+219#5867#5648
20K → Half537+46#5648#5602
Half → 25K26714+253#5602#5349
25K → 30K4339+424#5349#4925
30K → 20M14614+132#4925#4793
20M → 21M1658+157#4793#4636
21M → 35K4353-10#4636#4646
35K → 23M10439+65#4646#4581
23M → 24M7356+17#4581#4564
24M → 40K4860-12#4564#4576
40K → 25.2M2221+1#4576#4575
25.2M → Finish7330+43#4575#4532
TOTALS2414447+1967
📊

Passing Visuals

Category:
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🔥Passing Intensity

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🔄Passing Circle

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🌊Position Flow

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🏃Race Lanes

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Public Race Data

Boston Athletic Association

Boston Athletic Association

Mika Timing

Mika Timing